Modules are stored in a folder accessed by the kernel. Placing a module, whether manually or by using an installer into that folder - making it present in the folder - is "installed."
The Linux Kernel includes a large number of these modules as part of the build, including a large number that you do not use - in order to have universal functionality on the broad range of systems out there.
Present in the folder - does not mean your hardware supports those modules, correct.
I have a lot of concerns about this... Most often, I see output like this in regards to replacing 64 bit with 32 bit - usually disasterous.
I wish we knew more at this point.
But:
If you are fine with reinstalling, then resetting the above to use Radeon driver instead of AMDGPU (Which as a side question... You installed the AMD Supplied AMDGPU pacakge? Or were you referring to the included AMDGPU in the Linux Kernel?), I think it is the safest and easiest option.
Using TTY or Terminal, I wonder if this may be helpful at this time, too:
Now, we know what that warning was...
Brave Browser repository lacks the GPG key.
That is not relevant to the graphics or the TTY issue.
It only means that apt won't pull from that repository for updates until the key is verified.
We can check that after reinstall...