How to recognise fake virus notifications on my MacBook

There is no remote computer that can tell what's on any other computer through a web browser. It's a scam. Ignore and avoid that web site in the future.

If you mean these messages are sliding in the from the top right of the screen, a site you visited has given itself permission to send push notifications. Everything you're seeing is nothing but a scam.

Open Safari's preferences. Click on the Websites tab and then scroll down to Notifications. Clear any entries in the right hand window. You might find something similar in the Pop-up Windows heading below that. Block any you don't recognize.

Then if you want, uncheck the box below as shown here.

I personally can't think of any reason why I would ever want any website to push notices to me.

Open Safari and go to Safari > Settings > Websites > Notifications. You will have to scroll the sidebar down a bit to find the Notification section, then choose "Deny" on all websites that show Notifications are allowed.

Recognize and avoid phishing messages, phony support calls, and other scams - Apple Support

"… scammers use any means they can to trick you into sharing information or giving them money, including … misleading pop-ups and ads that say your device has a security problem"

Stop unwanted Notifications - Apple Community

Has the advice that Kurt Lang already gave you, plus illustrations of some typical scam messages. You may recognize them!

Federal Trade Commission – How To Spot, Avoid, and Report Tech Support Scams

"Tech support scammers want you to believe you have a serious problem with your computer, like a virus." The FTC gives an example of a pop-up window that tells you to call a phone number, and says "If you get this kind of pop-up window on your computer, don’t call the number. Real security warnings and messages will never ask you to call a phone number."

yea that happened to me too but that is totally fake it said it was McAfee but the website domain was moundunsus.com if you enter that into search bar nothing happens it gives about:blank but if you put this in **** then it says there is viruses and it wants you to renew subscription which is weird cause subscriptions autorenew and I also never installed mcafee so it was fake

[Edited by Moderator]

Great answer - many thanks. I couldn't believe what was in there!!! How could an xxx site be in there when I never, ever accessed any??? Thanks again

Thank you very much