Do nebulae create galaxies

Well... I guess you could say that...

Nebulae are just really gas clouds... usually they form stars (inside galaxies) but a large enough one could form a galaxy by creating enough gravitationally bound stars. It isn't likely to happen now though. It did happen frequently during the early universe where there was essentially nothing more than massive nebulae but now the average density of hydrogen gas means at most two or three stars at a time.