The main issue here is that Android phones were not designed for such games and playing can be difficult when you need to hold several buttons at the same time. Audio can get choppy at times and FPS drops can occur but you can always tweak some settings which can resolve these issues. The emulator can run most games with high performance even on lower-end Android phones. Some other emulators for Android need you to manually set up certain files and settings but PPSSPP can simply be installed and ready to use immediately. Inside PPSSPP settings, you can move and resize all buttons. There is a virtual button layout which includes all buttons from the original PSP and it's quite easy to use it. Once you get your hands on PSP ROMs, simply transfer them to your phone and you can use the built-in file explorer to search for them. However, these games are not worthy of downloading the PPSSPP app.
Of course, it doesn't contain any games by itself and the only way to play them is to transfer PSP ROM files to your phone or to play some user-created games from the PPSSPP Homebrew Store. PPSSPP is an Android app used to emulate PSP games.
Emulating PSP games on an Android phone is a popular choice so make sure you check out how to do so! And if you are on a mac, you can use a docker container: Install docker. If you are on linux, you have to compile it yourself. If you are on windows, use the romcnvmvs.exe executable provided. Some games must be pre-processed with the romcnv tool. Of course, your Android phone's characteristics should be better than the characteristics of the device you want to emulate, depending also on the game you want to run. zip games roms into: /PSP/GAME/mvspsp/roms. Price: $ Emulators for Android enable you to run games from other platforms on your Android phone.