I like this primer for Aluminum: https://www.westmarine.com/pettit-paints--aluma-protect-primer-kit--P014395917
For paint there are many options. For the bottom I would recommend steelflex; keeps the bottom in good shape better than paint.
People have used everything from porch paint to rattle cans on the top side. I am particular to the Parker's duck boat paint: Parker duck boat paint at Cabelas. The Marsh grass is a little more brown than regular olive drab, but I like it!
The Steelflex, the primer and the paint can be rolled and tipped; use a good high density roller and it goes on beautifully.
Once you get the old paint off, use a good cleaner like denatured alcohol before you apply the primer; right before you apply the primer.