Corvette engine problem

I have water bubbling out between the headers and the engine block (same place on both sides)of my 1980 vette 350. Will this problem go away with a rebuild or am I looking at a replacement? Thanks for reading.

It’s either bubbling out of a rotten freeze plug or -more probably- a failing head gasket. Either way, a rebuild is going to fix it.

I am somewhat new to this hobby, I did a lot of work on a 73 Mustang but mostly minor stuff. Is it normal to blow both heads at the same time? Any advice on rebuilding an engine for the first time?