First, welcome to the MD world.
I will offer a couple of tips I have learned. One detector I have is a Bounty Hunter Sharp Shooter 2. I hunt it all....Parks, gathering places, old home sites.....
I have found when you pass your coil over a "trash" target, that sounds like a target, if you will continue to swing the coil over it, until the coil hits the edge of where the target was first sounded, the tone will change to another tone......swing back over the target area centering the coil over the target and you get a good target sound again. Now as others have stated, you gotta dig the trash if you want the gold! But normally a coin and gold will sound the same tone if the edge of the coil hits it, or the center of the coil hits it.
My handle on here is Shiloh Trashdigger, and I am not ashamed to dig the questionable sounds. You will improve your trash to treasure finds, but I gotta tell you.....you gotta dig em
Also I have found on the flat crushed cans and jar lids, when you get that good silver signal, lift your coil in the all metal mode when pin pointing the target. If you lift the coil off the ground 10 to 12 inches, and you still are hearing the signal, it is gonna be a flat can or jar lid.
It takes time and patience. Patience and time. While hunting a city park this week, I found a gold wedding ring about 3 inches down. Yep, it sounded of a pull tab, but the signal was so good and did not change, I dug, and there was the gold ring, standing on edge.
Trust me, you will learn, but do not be deceived to think you will be able to never dig trash......it is nice to watch all the videos of diggers pulling silver coin after silver coin.....makes you think you are doing something wrong....but they find and dig trash too.
And let me leave with this thought. I love metal detecting. When I get my detector, my back pack, and my pinpointer, all my cares are left behind. To me, this is not about having the best detector on the market, every detector is a good detector. However, the detector is never any better, than the person using it. Metal detecting is not about getting rich. It is about the peace and enjoyment I get out of finding things under the ground that were lost and forgotten. Now do not get me wrong, finding valuables is nice, but for me, it is about quality and enjoying life. When it becomes more than that to me, I will be done with the hobby.
Hope that helps some. And glad to help with any other thoughts.