How to clean your selfie camera?

Hey, I bought a used Apple 12 Pro in September. It's in perfect condition; the display and battery have only been replaced once. The front selfie camera hasn't been working well for a while now; it's much more pixelated and has a slightly bluish tinge. The selfie flash doesn't work well at all. If you look closely, you can see lots of small dots behind the glass, so I suspect it's pretty dirty. Does anyone know how to clean it?

This is what the pictures look like 😭