Perhaps the following links will be helpful.
Additionally, you might find the gnome-disk-utility a useful abstraction from manual mounting.
sudo pacman -S gnome-disk-utility
NTFS3 is the default kernel module and should be loaded automatically; nothing extra to install. I should imagine it will just be a case of mounting your disk(s).
That said, if the disks are meant only as storage, I’d usually recommend formatting them with a native Linux filesystem (such as EXT4) instead.
Or, if they are meant simply to facilitate transfering files between Linux and Windows, consider EXFAT which is readable by both Windows and Linux (and MacOS too).
Disks can be re-partitioned and/or re-formatted using gparted, as one example.
Regards.
Welcome to the Manjaro community
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Output of the inxi command with appropriate parameters will achieve this (naturally, formatted according to forum guidelines) and will generally be more useful for those wishing to help:
inxi --filter --verbosity=8
or the short form:
inxi -zv8
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