Hey there, STEPHEN CANFIELD
If you feel as though your computer has been compromised, the first thing to do is to uninstall the software they have installed onto your computer. Once you have done this, please disconnect the computer from the internet.
When the computer has been disconnected from the internet, please click onto the search bar and search Windows Security
Please click onto open for Windows security
Once the Windows security app opens on your computer, please select "Virus & threat protection" from the left-hand navigation menu
Then click onto "Scan Options"
Please select the option to do an "Antivirus Microsoft Defender (offline scan)"
Then click onto "Scan now"
This will run a full offline scan of your computer. This scan will take around 15 minutes to complete and will look and try and remove any threats found on your computer. Once this scan has been completed, please connect back to the internet and sign into your Microsoft account security page here: https://account.live.com/proofs/manage/additional
Please make sure your security information is up to date. If any information is not correct, please remove it and replace it with the correct information.
Please scroll down to the bottom of that page and select generate a new code under the recovery code option. Please keep this safe as this will allow you access to your Microsoft account if you no longer have access to your security information.
I know this is a long winded post, if you need further help protecting your Microsoft account, please let me know.
Hope this helps,
Nathan