skiptut-
First off, welcome to iRV2!
Second, you should add a "signature" to your profile. It contains whatever info you want; most people put info about their coach there, so they don't have to type it into each message. Instructions for adding a signature are
here.
Per page 70 of the manual to which "Sweetbriar" referred, fuse 27 in the Power Distribution Box (PDB) powers both the high and low beam circuits. There are other fuses, but start there. Fuse 27 is a 30A MAXI fuse.
The PDB is under your coach's hood, in the center, against the firewall, towards the top. There are arrows on the PDB cover that point towards the PDB cover release latch.