

There are several apps/websites to learn touch typing from the start, you go from using 2 fingers in their proper places up to the whole hand with exercises that go up in difficulty over time, just do sessions of a few minutes each day and thats it.
my personal recommendation would be https://www.typingclub.com/
You could do this perfectly with the docker version, so just curiosity here, why not user docker?
Is it because you don’t want to install docker for only Immich? (you could also install other selfhosted server/apps as bonus),
would you be against snap? As someone already mentioned, there is a snap version.
If the important thing is having backups of your photos, there are alternative apps with different packaging formats.
You could make a request for flatpak, and see if other users also would like it, but you would have to wait for feedback from devs and understand if they don’t have the resources or willingness to maintain it.
If I’m interested in a specific app, I see what packaging formats it has and see how to install it and try it out. Only if I’m having issues with it (that can’t be solved), or can’t run it on my specific distro with the available packaging formats, I try to suggest/request a different format.