You would need to use a wet area approved wallboard, usually called "greenboard". This is an inexpensive sheetrock product. I would treat the entire wall this way, but it is mainly to protect the area above a standard tub enclosure, usually 74 to 78 inches up the wall.
There are superior greenboard alternatives like Durock and Wonderboard. You could try this stuff, but I find it harder to work with. It can be difficult to bury the screw heads without breaking off the screw head or tearing the protective sheet of the board, especially in old wood. I guess they now have special screws for this type of board, but it is still hard to screw without tearing the protective film. JMO
Ame's Research Paint & Prime® 25 Year is available from the factory at
Paint & Prime is different than the SuperPrimer product I talk about often on this forum. Paint & Prime is a true paint product, better than any I have seen for water protection. SuperPrimer is even better, but it does not roll on smooth like paint. Kind of a rough texture and not controllable enough to actually use for texture. Well, I am sure you could use it if you were creative, like blotting it or something. But the Prime & Paint will work very well and easier to use.