This is a discussion on How to play projects? within the online poker forums, in the Learning Poker section; How do you play after a flop comes out with good color projects or stairs? were they aggressive or do they check? what size of
I'm guessing you're asking if the flop has strong flush or straight draws, i.e., a wet flop. If you have a good pair or even a draw yourself you should probably check especially if there are multiple opponents. No point in making a small pot large if there's a good chance that you're going to be dominated on future streets.
Depends of the situation. In general you want equity just in any hand so if the pot is very small you should definitely raise a little bit but if it is large you should check cause if let's say player go with strong raise against you it can easily be tuned to be battle for all or nothing.