Yeah, RV's do not have an " owners manual" on how to operate all the mechanicals like you think of when you buy a car or truck..
That's up to you to figure out or the dealer that might charge a fee to spend an hour or two with you when you buy it brand new, or buying used.... Well, that's up to who sold it to you if you don't know how to use it and what questions you ask (either private sale or dealer)
You should be able to find the individual manuals for each appliance in your RV on how it operates on the interweb. So, that service you paid for should be able to find each individual appliance you have. You just gotta get the model number for each one..
That's all you get with a new RV even today.
All I got with my brand new 2003 Prowler was a packet full of the manuals of each appliance. Same deal on my brand new 2019 Rockwood..
In each of those new rv purchases, the dealer that sold me the rig took me thru it and showed me how to operate all the stuff..
In the end, I knew about some of the stuff, but even after 50 years of 'camping' experience, I needed to ask a lot of questions on these new "rv" stuff..
You Tube will show you tons of stuff on how to do the basic "rv stuff" if that's what you are looking for.
Good luck! Mitch
2013 F150 XLT 4x4 SuperCab Max Tow Egoboost 3.73 gears #7700 GVWR #1920 payload. 2019 Rockwood Mini Lite 2511S.