You bought from a dealer, correct(2019)? They should demonstrate all of the systems for you.
If there's water in your fresh water tank, run the hot faucet until water comes out. If you get water, the valve is open, there's water in the heater, so you can turn it on. If you get no water, you need to open the supply valve for the water heater. This valve should be downstream from the water pump...most likely after a 'T' in the supply line. Once you find and open the valve run the hot faucet again...
There should also be a manufacturers diagram of the fresh water system, showing which position all valves should be in, for regular use as well as water heater bypass(for winerization). Good luck.