1993 Toyota Camry How many heads in my engine?

My problem began with overheating, then white smoke coming directly out of the engine. It looked as though the smoke was coming from the front (or left) head. I know I must have a blown head gasket or probably a cracked cylinder head.

My question: There are two head gaskets to deal with, yes? No one ever says "heads" or "head gaskets". They always just say "head" or "head gasket". Are they talking about both or either heads, or one specific one? So am I supposed to replace both at the same time or do I just replace the left head gasket? (Or front head gasket, since it's a tilted Toyota engine).

Lastly, how do I know if the engine block is cracked?

Thank you