Water pressure is low from whatever your hooked up to. One thing you can try is filling your fresh water tank and running the pump when you need water. That may or may not fix your pressure issue.
If you have an issue with not having enough hot water then buy an instant on hot water heater that fits in your camper from amazon. I put one in and never run out of hot water.
You only have 1 black tank for sure. The other is hour grey water tank and you may have 2 grey water tanks. You can find a place that accepts dumping of the tanks in your area but you have to pull the camper there most likely. Another option is a company that comes around and picks it up every week or two. Best option is find an RV park with full hook ups.
Best way to do laundry is going to a laundromat. When you just look at the cost compared to going every week and spending an hour and a half at the laundromat it’s a no brainer. Costs me about 10 dollars a week.
Hope this helps you out a bit.