Best format and codec to use in my situation?

I want to send my friend an SD card with videos I took on my iPhone. Unfortunately, he doesn't have access to a computer at all right now, which means he needs to watch the videos on his point & shoot camera. I don't know exactly what model or brand, but it's one of those really basic $100 ones. It shoots video, but it doesn't shoot HD video or anything, only 480p.

I'm going to put the iPhone videos into Premiere Pro and I want to export them to the right file extension and codec for a regular point & shoot camera to read them. What is your best guess here?

There's no codec or process that will do what you want. A point and shoot camera can't even play the video or stills it captured once moved to a computer and copied to another SD card and re-inserted in the camera…

You can keep trying, but ot won't ever work.

Generally, step 1 for cameras and camcorders is to "format the memory card in the camera". There are several reasons to do this - one of them is a "database file" gets set up on the memory card. It keeps track of the stuff the camera captures through the camera's lens. That way it can play things back or display them. When you introduce a memory card that has images and video from another source (in this case your iPhone), there's no database and camera has no idea where things are on the memory card or what the files are that are there.

No "best guess" needed. What you propose to do will not work, period. This is positive 100% reality.

Point and shoot cameras will only play videos they have taken.