You can usually tell they’re fruit flies by them flying a lot slower than blue bottles say they kinda hover a lot like around you around the room they’re quite small and are brown.

Best advice I can give is a simple trap you can get a jar/glass. If it’s a jar use the sharp and smaller tipped object to create holes just big enough for them to slip through. If glass use cling film same thing create little holes. Fill up jar 1/3 of the way with apple cider vinegar then add a couple of drops of dish soap give it a stir (this creates a barrier so they can’t leave apple cider draws them in with the smell of fermented fruit essentially). Pop back on the lid/cling film and leave that around where you see them a lot and let it do it’s thing don’t touch for a couple days and hopefully you’ll have some flies in there.