Not sure how similar (or different) ours may be.
On mine there are two "pull-up" valves that are the "low point" drains for the lines. It helps to open all the spigots when doing this. As for draining the tank, there's a little stub of a line that drops down under the carriage in line with the gravity-fill hole; there's a little valve on the end of it. Just twist it and the tank will drain. To drain the water heater you need to pull (unscrew) the drain plug.
TT: 2019 Minnie Winnie 2500FL, e2 WDH; former 2015 Keystone Bullet Premier 19FBPR
TV: 2012 Ford F-250 Lariat Super Duty Crew Cab (gas 6.2 L, 3.73 gear ratio 2WD, 172" WB)