you only use primer over bare wood or stains. If you have really tough stains you might need to use shellac based primer, otherwise any stain covering primer.
Latex.
I would use Kilz latex primer.
It's primer made with a latex or acrylic base. You can use any kind of paint over this.
You can use either a water or oil-based paint over a latex primer.
Not directly. You will need to use a primer made to adhere to oil and will accept a latex topcoat.
Either oil or latex primer can be used over interior latex paint.
yes. However, you cannot use an oil base paint over a latex primer. If you change your mind on the paint, you must strip the paint before you use an oil based paint on the primer.
Yes, you can use either latex or oil based primer.
You have a contradiction ! - Latex primer CAN NOT BE oil based.
NO. -It will not stick.
NO ! - woodstain does not use a primer.
Primers of all sorts are fine over shackle. The most commonly used and available is latex primer.