Got some surface rust coming up on the rear arch of my daily runabout escort mk6, was gona sand it down 2 metal then cover it in a layer of paint!

Is this a good move? if so wot paint sud i use, red lead, normal primer etc!
If not a good plan, den ne other tips wud help!

The quater panel nears sprayin neway just aint got the money at the mo so wanna stop the rust 4 the time bein!

Cheers
Pez