Windows 10 Home ver 1803 Need to Change Settings but No Admin Password

ACER Laptop running Windows 10 Home version 1803 - this PC was handed down to me, and I haven't been able to find the Admin original PW. Have been using this PC for over a year, trying to work around the constant demand for the Admin Password. Recently used a tune-up program which automatically changed many of my Personal Settings, and now Windows simply won't allow me access to Settings or Control Panel in order to change them back, even back to Default. After two days of trying Every Imaginable remedy, I'm completely stumped for ideas as to what to do now? Any suggestions, thoughts, ideas would be VERY appreciated. Thanks!

Thank you, Brink. I was trying to avoid that! One main concern I had was, since the PC will reload right off of the Main Drive, and the PC itself was actually bought and set up by the original owner, would the Administrator remain the same? The original Program was Windows 7(I think), and I downloaded and installed Windows 10 while it was still a free Upgrade to Windows 7.