What type of sandpaper should I use on my 1963 Ford Fairlane?

I have a 1963 Ford Fairlane that i'm trying to redue myself. I need to know what type of sandpaper to use on the body to get some of the old paint off and then I need to know what to do after that?|||id use some 150 to take the paint off and then use something in the 200's to smooth it out and then wet sand it with something like 1500 to make it really smooth then put it in primer and go from there.