PCV/air breather to crankcase?

Ok so I bought this car and I keep getting a code po446 that's a small leak in the emmission or gas cap and there's a hard plastic hose that goes from the air intake to the back of the engine that at that spot was just loose and moving around so I'm assuming it's the cause for the leak so I try to get a gromet to fit in the hole and I loose that hose leaving autizone and nobody had a replacement but Amazon so I get it and now the piece going in the holes to big it goes in but pops back out as if there's pressure pushing it out so the guy at napa gives me this gasket/sealant maker that doesn't help either any ideas on what to do