I gotta agree with both of you to an extent. I don’t have the fuse box memorized on a whatever rv that is and neither do the rest of us.
But I agree, more info needed. Typical reply to most “help me” posts.
Also not all lights on the same circuit so unless multiple fuses simultaneously then I wouldn’t start there if the whole plug is dead.
Most likely if worked yesterday, all dead today scenario (again, very sparse info provided) I’d be looking at the grounding.
Is 7pin grounded to chassi or pass thru to trailer. Is trailer ground connection(s) good? Is the ball grounding good to the tongue (or too full of rust or grease to make a reliable connection)?
OP needs a test light and or a multimeter and a basic understanding to 1. Provide more info. And 2. Actually use the tools and suggestions to diagnose.