The Master switch is a 3-position switch. The bottom of it should be "in" for the top to raise or lower. You put that switch in that position and then toggle the raise/lower switch to get the thing up or down.
If it doesn't move, you likely have a dead battery. It will have to be recharged before the top will raise electrically. AC power or tow vehicle power is not enough to do it, due to the way the onboard battery charger/converter handles charging current.
You turn the fridge off by pushing on the "off" sensor, or turning it off at the appliance, depending on your fridge model.
There should be a "gas" selection on the fridge too. On mine, you toggle between that and "auto". In auto, it will run on AC if connected, or on DC if not connected to AC.
Yes, put your hand underneath the wheel to back up. BUT - as soon as the trailer starts to turn, turn the wheel in the OTHER direction so the tow vehicle will follow it, but not too far, or you'll straighten the trailer's path out again. If you don't "countersteer" at the appropriate point when the trailer starts turning, it will jackknife, and, you'll have to pull forward and start over. Usually, about the time you can tell the trailer is turning, it's time to countersteer.
Have fun with this!
Hi-Lo 1707T - Tire Minder TPMS on Tow Vehicle and Trailer, 300W Solar Battery Charger, Equal-i-zer WDH
2014 F150 Platinum 4x4 3.5L EcoBoost SCrew