@valentina
Only use a usb 2.0 port on pc and usb 2.0 cable during the installation. I made this mistake when I installed my pixel 3A. The installer only works with usb 2.0 not usb 3.x. Tick both Wipe userdata and Bootstrap.
@cibersheep
Terminal is installed by default on ubports Ubuntu Touch, but maybe as it's "unused" he's still on a canonical one, where it was not.
Maybe first he should update to last ubports UT update ^^