What does the little “fn” in the top right corner of my iPad screen mean?

iPad Air 5th gen OS 17.0.1

Smart keyboard

I just recently got a smart keyboard for my iPad, and there are a few symbols that have been popping on the top right corner of my screen everyonce in a while. They all go away on their own immediately except for a little “fn”. Im curious as to what that means if you happen to have an answer for me? And if you have the time, maybe explain the other icons that happen to pop up as well, please. That would be greatly appreciated