Does the engine alternator charge house batteries?

Thank you guys. We are on our trip to Florida so far, going in Tennessee right now, and everything is working great as it should. We sleep in hotels because we have 8 people on board.

I have one unrelated question: This Windsor Monaco 40 PST has auto trans and a "Engine Brake" button.

The engine brake does work on long downhills.

However, I am not sure what it means: does it mean a "Jake Brake" (pneumatic), or just using a higher gear to slow down the RV with the engine and transmission?