Welcome to the wide world of RVing.
And you are right there is a pretty large learning curve with many lessons being taught by making a mistake. The good news is that with the internet to search, study and read most mistakes can be avoided. Got a question, just ask. You will get answers, then the secret is to select the right answer some times.
There is a Wildcat sub forum here on this site located here:
Wildcat - Forest River Forums
Keep in mind that most RV issues are pretty generic in nature so do explore all the various sub forums here on the sight.
On the interior side wall under your TV hook up feel around there should be a backer board behind your interior finish wall that would allow you to mount a bracket for hanging your TV. Or at least there is on 95% of RVs.
ON the subject of water pressure, is yours too low or ?