How should I attack this wall?

[Stephen Spradley]

Hey BP, 

I’m about to find myself with a lot of free time and thought it would be a good idea to knock out one of the projects in a home I recently purchased. We are tearing these wooden boards off from the bottom half of the wall, and I definitely underestimated how many layers would be pulled off. Since I have no drywall experience whatsoever, other than paint, I have a few questions that hopefully somebody who knows what they’re doing can answer. 

- What would be the best way to handle the top layer that’s still painted? I was planning on just taking an electric sander to it and going to town.

- What’s the product I’ll need to apply to the cardboard looking layer when I knock all the edges down? 

- What is the easiest way to texture? 

- Should I stop while I’m ahead and just hire a pro? 

I really appreciate any advice you guys have. Thanks!