With those hobbies I'm also guessing you lean toward being introverted. (Not to be mistaken for shy...but I digress.)
Covering the hobby in a few paragraphs is impossible. First rule is you will dig junk and lots of it.
Second rule dig enough holes and you will find something amazing. (Unless you have beginner's luck and find gold on your first target.)
The first question new people ask is, what machine is the best. Wrong question. You should ask what are the different types of metal detecting and how does each match me or where I live or regularly travel. IMO the three most popular types of hunters here are relic (civil war being a huge subset of relic hunters), beach and water hunters, coin shooters/jewelry hunters. I will say this...the guys in Europe make us Yanks look like amateurs when it comez to old stuff.
Amount of time you expect to hunt? Both how often and time per outting. This will play a role in how much you want to pay for a machine and iits weight. Even a few ounces add up on a ten hour day at the beach. But won't matter on short 30 minute hunts.
Get copies of all the catalogs from the major brands. All have decent machines. Avoid radio shack machines.
Don't get a machine with every bell and whistle as a first machine. You'll want a machine that you can learn without a degree.
Don't overlook used machines. ..lots get bought and then live in closets.
If you can go to an actual metal detecting shop, its worth the trip.
Read and ask questions here. Lots of people will help.