Does a 92 prelude with an h23 have the same starter as a 94 prelude?

Yes

yes as long as it has the same block # if not u have to change ecu

Yes

If you are replacing a H22 engine with a later H22 variant it can be done but requires other items to be replaced. Research research research, check the car forums.

92-96 Hondas in general have OBD1, not OBD2 and therefore no OBD2 / diagnostics plug.