Do I need fasteners to bolt this on?

You'll need hardware to secure the bar at factory mounting points. The bar itself ships without bolts — grab M8 or M10 hardware (depending on your factory holes) and you're set for installation.

Can I paint this before or after install?

Paint after install. Mounting and torquing can scratch the finish, so get the bar bolted down first, then mask off the attachment areas and spray your color match. Clean the surface with soap and water before priming.

What if I need to replace my bumper cover later — does this bar stay on?

Yes. The reinforcement bar bolts to the frame and stays permanently. If you swap your bumper cover, the bar remains in place. You'll just need to align your new cover around it.