ok, then somehow a password ***** set and if you cannot recall it then you will need to reset the computer
this will remove all data from the computer and return it to new, but you cannot avoid this, it is the whole reason for the security
To do this, on the sign in page, hold down the left SHIFT and with it held down, click on the power icon and click restart.
Keep shift held down until you are at a menu.
Choose Troubleshoot, then Reset MY Pc.
You have to choose to remove files, then let this complete, windows is installed again and you can set up and use the computer
Let me know please how you go.