Hacking a PSP is super duper easy, you just need to follow some guide you find on Google, here I spotted one on Wololo:
https://wololo.net/installing-pro-cf...1000-psp-phat/
You can roll your firmware up and down as you please, so just roll up to 6.60 like the guide directs you to, there's no downside to doing so. As the guide says, you only need to follow the first 3 steps. Step 5 is totally pointless, as the guide says.
Once you have CFW you can just Google for an emulator you'd like, just search something like "best PSP SNES emulator" and you'll find SNES9X somewhere. Or alternatively and more easily, we have emulators here which still have working downloads (but I'm not positive they're the latest builds, but there hasn't been much development in years...):
https://www.emuparadise.me/Emulators.php
Just click the system you'd like to play, like SNES, then click PSP as the platform you'd like to play on and pick the emulator you'd like.
