Shows only “/dev/sda2 clean”
Alt+F2, Alt+F3 and etc doesn’t show anything
EDIT: I installed it three times, but sys folder on hdd is empty, maybe this is a problem?
Sounds like you didn’t install correctly. I’d boot up your USB and try again.
this sounds like either a grub or kernel boot error. It’s really hard to work out exactly what the error is when you get stuck on that screen.
Depending on how familiar with Linux you are, you could boot to a USB and access the log files on the disk to find an error or you could just go with a reinstall and ensure you have selected the correct boot device and secure boot if turned off in bios.