Where's the bypass for the water heater?

Google "rv water heater bypass diagram" and look at the pictures.
As for the freshwater drain, look underneath the trailer directly below your water fill point. The drain valve may be on the other side of the trailer but it should be around that point in the trailer.

Does every water heater have a bypass? Seems like an easy way to save manufacturing cost by not supplying one?

If you can find the FW drain, just run a faucet until it’s empty and then dump the gray tank. It will empty faster that way anyway.

There are different variations of bypasses. Most I have seen have been located on the back of the water heater. Sometimes you have to remove an access panel or drawer to get to them. They are generally a series of two or three valves. There is generally a cross over pipe between the ingoing water line, and the line leaving the hot water tank. You generally close the one going to the tank, and if it has three, you close the one leaving the tank. You then open the one that diverts the cold water from the inlet pipe to the crossover to the outlet pipe, thereby bypassing the tank. Some have valves in the water bay, but I think they only install them on higher end class A.

1. The water heater by-pass is usually near the water heater tank. It's the red thingy lever. So, as I tell my 4th grader, if it is usually on, so turning it the other way will shut if off, lol.

2. There are drain tubes for fresh water tanks underneath your unit. Open it up and set aside the plug and water will drain. Mine have 3 of them for municipal water, fresh water storage tank and hot water tank or lines.

And welcome to RVing.

Wait for the fun part, dumping and draining the dark water tank.

A complete search of the underbelly of your trailer didn’t locate the fresh water drain value? (On your back with eye protection)