Can they get mouth rot this young he’s about 2.5 months old and I haven’t seen anything wrong with his mouth before this to me it looks like a hole like his mouth isn’t closed all the way I can get some more pictures from different angles later
If you work quickly to solve it you might avoid a vet visit.
The usual bacteria found in mouth rot is pseudamonas aeruginosa and once it gets a foothold it's hard to get rid of.