"Activate Windows - Go to PC settings to activate Windows" is likely a watermark you are seeing if you upgraded from Windows 10 build 10056 to Windows 10 build 10061. So how do you get rid of this watermark? Easy, follow these steps.
Simply launch command prompt with administrator privileges and run "slmgr.vbs -ipk PBHCJ-Q2NYD-2PX34-T2TD6-233PK". Make sure you are running command prompt with admin rights or this will not work.
Once you enter this command, reboot and you will no longer see the watermark. If you are still facing the issue, let us know in the comments below!