Please help with Body Prep / Engine Bay

I have a really nice no rust California 1974 Dart Swinger. I have the drive train pulled and I am rebuilding the front and rear suspensions. I would like to save some money and do some of the body prep for paint myself. My biggest issue is that I know nothing about body work.

My question is where do I start? Can I clean up and sand the original paint down to a point or do I need to go to bare metal for a quality job? What type of primers and in what order. At what point do you start with filler to smooth small imperfections?

Any advice or help would be great.

Thanks!!!!