If your microwave is not on, you're not on shore power. In fact, the beeping of the microwave as it turns on is how we know the shore power is working.
If you're putting in a 30 amp, make certain it's wired properly for an rv.
Most things in your rv will run if you plug it into household current using one of these.
https://www.amazon.com/Camco-PowerGr...715399484&th=1
Obviously, the ac probably won't work and you might not be able to actually use the microwave, but the electric start on your fridge, water heater and your ac outlets will work.