I metal detected for a few years, but haven't been out in a while, got involved in a few other things. I live in Florida, so only have a few months of ideal outdoor weather to play with, then it's hot and sweaty, or rains a lot. It's fun, but can be a lot of work and disappointment too. There are rules and regulations for places you can detect, some places are completely off limits, and some serious consequences if caught. The metal detecting forums aren't great for getting straight answers, pretty sure many of those people type more than hunt, mind wanders a lot while out swing that coil back and forth. I stopped using those forums after a while, too much bad information being shared, some was more of a joke, but some actually believe, nobody corrects them. Historical sites, like old parks, are usually off limits, but some of the jokers would suggest to go a night. Lot of other advice, figured was mostly fantasy, and probably get some people in trouble. Of course, with any hobby, the newest, and most expensive, is always the best, and everything is junk.
The reality, is there is tons of trash out there, most of which can sound, and register like something good. You never really know, until you dig it up. Sometimes even a piece of rust junk can look pretty cool. Who knows, it might sound like a rusty can, the screen says iron, but it's a can full of coins. Basically, if you are only interest in silver and gold, and set up you detector to reject everything else, you'll mostly just be walking around, when it does beep, it can still be trash. You get better at listen to the tones over time, there are some subtle differences, if you get tired of digging trash, but can still some good stuff. Learn that in my own yard, a few times. My house was built in 1946, so figured there should be some silver, only one dime though. Did find quite a few more modern coins though, real close.
My thing was to hunt the little strip of grass, between the street and the sidewalk, grass median too. I live in a small town, don't get a lot of attitude from people. That little strip is a mystery to most, as to who actually owns it, and what can be done there. Never had a problem or foul word, but I didn't make a mess, skip over sections people took real good care of, and didn't stay too long in one spot. Usually not a lot of trash, coins, some interesting items, lot of keys. I never really found a lot of silver and gold though, one wedding band, a few sterling silver pieces. Nice St. Christopher medal. Several pieces of chain, never bothered to get tested, one is probably gold, yellow all through, not discolored (green). It's adventure, sometimes you get rewarded, but mostly don't expect too much, more fun that way. Parks are usually pretty trash, not very productive for the work, and you need to be extra careful to fill you hole back nice. Tough to do in our sand, we call soil. The few times I went to parks, I asked the attendant first, to make sure it was okay, usually, don't make a mess, stay off the sports field. Only had a few people that didn't seem too thrilled with what I was doing, but they didn't push. It's a small town, people have their opinions, be tend to respect others for theirs, long as you aren't doing any harm. You basically need to get out and try different places, see what works best for you. Be respectful of others, even though it's public property, somebody is responsible for taking care of it. Best to ask first, usually showing that little bit of respect, will get you a positive result., if possible. Some places are just off limits though, you should respect that too. Plenty of places to go, no need to get sneaky.
You best bet, is where people gather most. Some places, like parks, probably the beach, attracted the trashy kinds of people, which makes for more work. Most people try not to drop their valuables. Another thing about the beach, they have machines that they drive around, and sift through the sand, to collect trash, and everything else. They don't go very deep though. Sometimes big storms drag a lot of sand off the beach, and you get a shot at some old stuff. Sometimes the storms bring in more sand... It's a lot of luck and persistence, appreciate what you find.
Anyway, suggest you spend some time in your own yard at first, practice and play a little with your new toy. You can do what you want there. Need to learn to dig clean holes, that you can put back close to how it was, grass on top. Filling your holes in, even at the beach, is an important skill, usually what others might complain about most. You'll want to take the trash with you as well, you dug, it's yours to dispose of proper, besides, you might want to go through there again sometime (you never get it all, some places replenish), pointless to keep hitting the same piece of trash each time. Really, no way for anyone to know your comfort levels, something you have to find for yourself. You don't really need a fancy, expensive machine, just learn the one you have, takes time to learn to listen to it. Garrett makes good detectors, big company, all they do. I never owned one of theirs though, went with another brand. I never really trusted the computerized stuff, if you never dig the hole, you never know what you passed up. Fine, if you are looking for something specific, willing to walk around and wait for the machine to find a sure thing for you. I wanted gold an silver, but plain coins are fine too, not to mention unusual items. Chains and jewelry can ring up as anything. The deeper the item, the less reliable the computer ID. Its a very weak return signal, gets weaker with depth. I prefer to go with the sounds, lot of variations, but you can learn over time.