How can I prevent rust?

About to do some more trimming along the cab mount cuz my tires were still grinding.
I noticed a bit of rusting where the metal is being exposed. I think someone told me about a paint or type of coating to prevent rusting, anybody know how to solve this?

 

For the past two years, twice a year, I will buy enough spray cans of Rust Oleum rust converter to cover the entire frame and any additional metal parts on the underside of my truck. They run about $6-8 if I remember correctly. First powerwash the frame or metal to the best of your ability. Then I spray the rust converter on, let it dry for a day, and then coat whatever metal I don't want to rust in Fluid Film. Granted I live in Montana now, but the truck survived about five years in Washington and Iowa before I bought it so it had a decent of amount of surface rust on the frame. Since I started this process two years ago, I haven't seen any rust. I try to do this after the snow is gone for the year in mid spring and then again in mid-fall before the snow starts coming again. That way the Fluid film has plenty of time to soak into the frame and metal parts.

 

Thanks, gonna go pick up some rust oleum.

 

For all things rust:
https://www.tacomaworld.com/threads/rust-prevention-treatment-consolidation-thread.355928/

 

move to arizona/socal

 

Yep move to the Southwest but with the strange weather and fires

 

Some type of oil based protection. WD40, fluid film, etc. I usually keep rustolium bed liner around to cover bare metal, and then fluid film in the fall and spring.