Windows 8, 8.1, 10 and 11 come with an improved Windows Defender, it offers the same real-time anti-virus/anti-malware protection as Microsoft Security Essentials. Windows Defender also shares the same malware signature definitions as Microsoft Security Essentials, and Forefront Endpoint Protection. Technically, Microsoft Security Essentials has not been renamed Windows Defender, or combined with it in Windows 8, 8.1, 10 and 11.
If any AV product that you have is a paid for version you should always make sure that you have a copy of the product key kept somewhere safe just in case you ever wish to reinstall it.
McAfee product removal tool (MCPR)
here
After McAfee has been correctly uninstalled, check to see if Windows Defender has auto enabled and allow it to update and carry out a full scan of your computer,
How to run a Defender scan read the full article before following the Run a malware scan manually steps.
Once done, restart, test by using the computer as you normally would, post back with an update when you are ready.