Hello Momo_54,
Good day! I'm John Dev a Windows user like you and I'll be happy to assist you today. I know this has been difficult for you, Rest assured, I'm going to do my best to help you.
Microsoft has made some great improvements and developments over the last few years when it comes to Windows Defender making it a great security software these days. It will not slow your PC, it is Free and will work for most of the web browsers like Chrome. I recommend not to renew your subscription with McAfee and start using Microsoft's built-in Security software.
Kindly let me know if this helps or if you have any further concerns.
Kind regards,
John DeV
Independent Advisor