Welcome!
Like Ken said it's always a good idea to remove paint (or avoid painting that area) where you're going to glue/bond.
However... I'm using
Tamiya paint and I "glue" everything plastic with
Tamiya extra thin cement, which is just a solvent that's dissolving the plastic, and it works fine through the paint!
It leaves bad marks on the paint though, but I can glue a piece to a painted object without problems. This is something I only do when I have to - like when I've forgotten something and not noticed it until after I started painting it...
It's also useful if you break something.