As you've said, there are tools on the internet. But as you've also said, you don't know whether they'll work. It really depends on whether your phone has those vulnerabilities and whether they've been patched yet (the internet is also a great store of obsolete information). The whole point of FRP is to deter theft, which doesn't work if it's easily bypassed, so they do patch these things as they are discovered. All I can do is wish you luck.
Some stores can reset it, if they have the right tools and authorisations. Whether your local repair shop can is another matter, though if they are honest they'll be able to tell you straight away.
FRP has been on all new phones for about 5 years now. The solution is to remove the account from your phone before resetting it (or remember the login details). I do wish that they'd spell this out more visibly and unmissably, because there are still a lot of people who don't know about it, so problems like this are quite common.