Emulators and the Steam Deck

So I recently purchased my steam deck and started playing around with it to see what I could do. Lutris was one of the suggested programs to install on Linux and I figured why not?
Here’s my issue: I’ve never used Linux before; add in the steam deck and I’m totally lost. I tried to use the emulators in lutris for the PSP and the GBA, but obviously they’re not set up to use the deck’s controls. I tried to use the virtual keyboard, but the moment the emulators start in the desktop mode all controls stop working. I had to hard reboot both times I tried.
I’d appreciate if sometime could guide me in creating a control setup that can work on the deck with this.