Newcomer requesting help! I am unable to get retroarch to actually DO anything

Good evening everyone. First allow me to apologize for any and all inconvenience my thread is about to cause, but after searching the forum for a while, I haven’t been able to find a basic tutorial thread stickied anywhere, so I came here to ask my questions. Feel free to scorn as much as you want.

I downloaded RetroArch 1.2.2 on my Huawei P8Max (currently running on Android 5.1.1, or rather EMUI 3.1, Huawei’s overlay) and a rom supposedly running on PSP. I then proceeded to update EVERYTHING the updater would let me update, including cores for every console ever to be played.

But when I tried loading a core or content, RetroArch does show me the downloaded content, but does not allow me to actually DO anything with it. What is the apropriate procedure in order to get to play with something please?

Pretty please? Pretty pretty please? (would probably bat eyelids if it helped, but I seriously doubt a 200-pounds bearded guy doing so would attract simpathy over immediate suspicion.)

Thanks in advance

The typical process is: download a core from the updater, load a core (that is, pick an emulator), load content (i.e., pick a game) for the core.

this is what I thought I did, but it appears the file I unzipped did not have an .iso file in it. I just downloaded another and everything worked. Now, all I have to do is figure a way to use my fingers in such a way that my ring finger will find itself at the top of the screen, in order to emulate the L1, L2, R1, R2 buttons…