To make a game u need an engine , right?

Answer 1

Not necessarely all sorts of games need an engine. 2D games for apps or pc don't need it for exemple

Answer 2

You don't need, but it is good to use one. An engine is nothing more than a set of premade functions to help building games. But you can build games from scratch, if you want.

Answer 3

hmm, those engines how did they make them??
by coding them, so no you do not need an engine, but it makes life a lot easier in some aspects I believe.

have you seen the popular Unreal Engine which is free to my knowledge ? ;)