Hi everyone I'm new here and new to owning a truck. I've owned my 2010 F150 for 1.5 years and it had minimal rust when I bought it (in Canada). I had it Krown underbody sprayed when I bought it and thought it would be fine but now after this past winter the rust has become pretty bad out of nowhere. At first I thought I wasn't going to keep the truck (a few months back) but I've realized now that I would rather put in the time and effort to keep it going because there's no point in trying upgrade in these crazy market prices for newer trucks.
So I will lay out the issues and my plan for resolving them and would love any feedback on if I'm on the right track or not. Greatly appreciated.

Issues: 1) Frame has surface rust 2) Outer rocker panels rusted out 3) Rocker cab rusted out

Solutions: 1) For the frame I was planning on wire brush sanding out the rust, then spraying it with fluid film or por15. Not sure if I would need to apply any other products?
2) Wire brush/sand down the rust on the rocker panels and cab and cut out the remaining rust pieces with a angle grinder. Next step would be to again apply some rust prevention products. I then was thinking it would be best to replace the panels with a slip-on panel from OAM https://oamusa.com/collections/09-14...cker-cover-kit

I am pretty good with my hands but not the most knowledgeable on trucks (yet) or welding/have the tools for that so I wasn't thinking to replace with new metal.
One tip I read about was that the rocker cabs have a drain valve that needs to be redirected so that they don't rust out?

Pictures of the current state of the truck are attached and once again I really appreciate any advice, tips, or help.
Thanks!