I don't see an option to mount 2 of my hard drives

  Kernel: 5.8.1-3-MANJARO x86_64 bits: 64 compiler: N/A 
  parameters: BOOT_IMAGE=/boot/vmlinuz-5.8-x86_64 
  root=UUID=466e087b-f546-49db-b3d2-7a6d47f3a8ec rw quiet 
  apparmor=1 security=apparmor udev.log_priority=3 
  Desktop: KDE Plasma 5.19.4 tk: Qt 5.15.0 wm: kwin_x11 
  dm: SDDM Distro: Manjaro Linux 
  Type: Desktop Mobo: ASRock model: Z370 Extreme4 
  serial: <filter> UEFI: American Megatrends v: P3.10 
  date: 07/04/2018 
  Device-1: sony_controller_battery_90:89:5f:3e:b5:1d 
  model: N/A serial: N/A charge: N/A status: Charging 
  Topology: 6-Core model: Intel Core i7-8700K bits: 64 
  type: MT MCP arch: Kaby Lake family: 6 model-id: 9E (158) 
  stepping: A (10) microcode: D6 L2 cache: 12.0 MiB 
  flags: avx avx2 lm nx pae sse sse2 sse3 sse4_1 sse4_2 ssse3 
  bogomips: 88824 
  Speed: 800 MHz min/max: 800/4700 MHz Core speeds (MHz): 
  1: 800 2: 800 3: 800 4: 800 5: 800 6: 800 7: 800 8: 800 
  9: 800 10: 800 11: 800 12: 800 
  Vulnerabilities: Type: itlb_multihit 
  status: KVM: Split huge pages 
  Type: l1tf mitigation: PTE Inversion; VMX: conditional cache 
  flushes, SMT vulnerable 
  Type: mds mitigation: Clear CPU buffers; SMT vulnerable 
  Type: meltdown mitigation: PTI 
  Type: spec_store_bypass mitigation: Speculative Store Bypass 
  disabled via prctl and seccomp 
  Type: spectre_v1 mitigation: usercopy/swapgs barriers and 
  __user pointer sanitization 
  Type: spectre_v2 mitigation: Full generic retpoline, IBPB: 
  conditional, IBRS_FW, STIBP: conditional, RSB filling 
  Type: srbds mitigation: Microcode 
  Type: tsx_async_abort 
  mitigation: Clear CPU buffers; SMT vulnerable 
  Device-1: NVIDIA GP102 [GeForce GTX 1080 Ti] 
  vendor: eVga.com. driver: nvidia v: 450.57 
  alternate: nouveau,nvidia_drm bus ID: 01:00.0 
  chip ID: 10de:1b06 
  Display: x11 server: X.Org 1.20.8 compositor: kwin_x11 
  driver: nvidia display ID: :0 screens: 1 
  Screen-1: 0 s-res: 5120x1440 s-dpi: 108 
  s-size: 1204x342mm (47.4x13.5") s-diag: 1252mm (49.3") 
  Monitor-1: DP-2 res: 2560x1440 dpi: 109 
  size: 598x336mm (23.5x13.2") diag: 686mm (27") 
  Monitor-2: DP-4 res: 2560x1440 hz: 144 dpi: 109 
  size: 597x336mm (23.5x13.2") diag: 685mm (27") 
  OpenGL: renderer: GeForce GTX 1080 Ti/PCIe/SSE2 
  v: 4.6.0 NVIDIA 450.57 direct render: Yes 
  Device-1: Intel 200 Series PCH HD Audio vendor: ASRock 
  driver: snd_hda_intel v: kernel bus ID: 00:1f.3 
  chip ID: 8086:a2f0 
  Device-2: NVIDIA GP102 HDMI Audio vendor: eVga.com. 
  driver: snd_hda_intel v: kernel bus ID: 01:00.1 
  chip ID: 10de:10ef 
  Device-3: Sony DualShock 4 [CUH-ZCT2x] type: USB 
  driver: snd-usb-audio,sony,usbhid bus ID: 1-3.2:4 
  chip ID: 054c:09cc 
  Device-4: Focusrite-Novation Scarlett 2i4 USB type: USB 
  driver: snd-usb-audio bus ID: 1-9:6 chip ID: 1235:8200 
  Sound Server: ALSA v: k5.8.1-3-MANJARO 
  Device-1: Intel Ethernet I219-V vendor: ASRock driver: e1000e 
  v: 3.2.6-k port: f000 bus ID: 00:1f.6 chip ID: 8086:15b8 
  IF: eno1 state: up speed: 1000 Mbps duplex: full 
  mac: <filter> 
  Local Storage: total: 5.03 TiB used: 470.61 GiB (9.1%) 
  SMART Message: Unable to run smartctl. Root privileges 
  ID-1: /dev/nvme0n1 vendor: A-Data model: SX8200PNP 
  size: 953.87 GiB block size: physical: 512 B logical: 512 B 
  speed: 31.6 Gb/s lanes: 4 serial: <filter> rev: 42AZS6AC 
  scheme: GPT 
  ID-2: /dev/sda vendor: Seagate model: ST3000DM008-2DM166 
  size: 2.73 TiB block size: physical: 4096 B logical: 512 B 
  speed: 6.0 Gb/s rotation: 7200 rpm serial: <filter> rev: CC26 
  scheme: GPT 
  ID-3: /dev/sdb vendor: Samsung model: SSD 860 EVO 500GB 
  size: 465.76 GiB block size: physical: 512 B logical: 512 B 
  speed: 6.0 Gb/s serial: <filter> rev: 3B6Q scheme: GPT 
  ID-4: /dev/sdc vendor: Samsung model: SSD 860 EVO 1TB 
  size: 931.51 GiB block size: physical: 512 B logical: 512 B 
  speed: 6.0 Gb/s serial: <filter> rev: 1B6Q scheme: GPT 
  ID-1: / raw size: 460.89 GiB size: 452.66 GiB (98.21%) 
  used: 186.48 GiB (41.2%) fs: ext4 dev: /dev/dm-0 
  Kernel: swappiness: 60 (default) 
  cache pressure: 100 (default) 
  ID-1: swap-1 type: partition size: 3.81 GiB 
  used: 1.8 MiB (0.0%) priority: -2 dev: /dev/nvme0n1p8 
  System Temperatures: cpu: 45.0 C mobo: N/A gpu: nvidia 
  temp: 58 C 
  Fan Speeds (RPM): N/A gpu: nvidia fan: 33% 
  Processes: 318 Uptime: 1h 43m Memory: 15.57 GiB 
  used: 3.52 GiB (22.6%) Init: systemd v: 245 Compilers: 
  gcc: 10.1.0 Packages: pacman: 1295 lib: 370 flatpak: 0 
  Shell: Bash v: 5.0.18 running in: konsole inxi: 3.1.05

I’m currently unable to mount my 1tb samsung 860 evo ssd and my 3tb seagate hdd. If anyone has any idea what’s wrong, it’d be really helpful. I’m new to manjaro but I have a little bit of experience in other distros like ubuntu and mint. If there’s any other info that I can post that might help, please let me know and I’ll post it.

Do you have any mountable partitions/filesystem on those two drives?
Please post output of

$ lsblk -fs
$ parted -l
sda1 ntfs         second
│                       595348487248A28A                                    
sdb1 ntfs         500gb sata
│                       9AF28A50F28A3095                                    
sdc1 ext4   1.0   mint media
│                       897e2cf4-a57a-4d0b-aec1-9f7823b4d0ff                
│    ext4   1.0         466e087b-f546-49db-b3d2-7a6d47f3a8ec  243.1G    41% /
     crypto 1           98731595-07e7-49db-8cec-31aa02e3ea9a                
│    ntfs         Recovery
│                       98E4078DE4076D36                                    
│    vfat   FAT32       420E-0281                              63.3M    33% /boot/efi
│    ntfs               6888294088290E5E                                    
│    ext4   1.0         92e2ce0f-7690-4a75-b8d5-78c32b54c301                
│    swap   1           0eb23ae5-45fa-4768-b0ec-4202233045bc                [SWAP]

I should have mountable partitions but I can’t seem to figure out why I can’t mount them. They worked fine on mint for me.

Model: ATA ST3000DM008-2DM1 (scsi)
Disk /dev/sda: 3001GB
Sector size (logical/physical): 512B/4096B
Partition Table: gpt
Disk Flags: 

Number  Start   End     Size    File system  Name  Flags
 1      1049kB  3001GB  3001GB  ntfs               boot, esp

Model: ATA Samsung SSD 860 (scsi)
Disk /dev/sdb: 500GB
Sector size (logical/physical): 512B/512B
Partition Table: gpt
Disk Flags: 

Number  Start   End    Size   File system  Name  Flags
 1      1049kB  500GB  500GB  ntfs               msftdata

Model: ATA Samsung SSD 860 (scsi)
Disk /dev/sdc: 1000GB
Sector size (logical/physical): 512B/512B
Partition Table: gpt
Disk Flags: 

Number  Start   End     Size    File system  Name  Flags
 1      1049kB  1000GB  1000GB  ext4               boot, esp

Model: ADATA SX8200PNP (nvme)
Disk /dev/nvme0n1: 1024GB
Sector size (logical/physical): 512B/512B
Partition Table: gpt
Disk Flags: 

Number  Start   End     Size    File system     Name                          Flags
 1      1049kB  556MB   555MB   ntfs            Basic data partition          hidden, diag
 2      556MB   660MB   104MB   fat32           EFI system partition          boot, esp
 3      660MB   676MB   16.8MB                  Microsoft reserved partition  msftres
 4      676MB   524GB   524GB   ntfs            Basic data partition          boot, esp
 5      524GB   525GB   1024MB  ext4
 6      525GB   1020GB  495GB
 8      1020GB  1024GB  4096MB  linux-swap(v1)                                swap

Well they are both there at sda and sdc
What do you mean that they arent mounting?
They arent visible? You attempt a mount and it fails? or ?..

They weren’t visible for me but I was able to retrace my steps and realized that I had applied the “boot” flag to both of them. I unchecked it on both and now they are both visible for me.

Just FYI, bookmark this post, or write down what you did to solve it, It’s sure to pop up again, and you will have the answer.