I have Virus on my Mac how do I do to get rid of it.

"Nice computer you got there. Too bad if something should happen to it."

You are being lied to by criminals who are sending you a message that is intended to panic you into buying their 'protection' or compromising your computer or your financial data.

There is no need to reformat your Mac, the message is a lie.

quit the page you were surfing when the massage appeared, or quit Safari, or force quit Safari.

Hold shift as you re-launch to NOT open previous web sites.

Before you open anything, Check:

Safari > Preferences > Websites > notifications ...

Delete any that you did not deliberately enable and use all the time.

Stop unwanted Notifications - Apple Community

junaidjabbar wrote:

Here's how to remove a virus from a Mac:1.

Disconnect from the internet.

2. Reboot in safe mode.

3. View the Activity Monitor.

4. Uninstall recently added apps.

5. Run a virus scan.

6. Check your browser homepage and delete your cache.

Delete unwanted browser extensions.1.

2. Restore from a backup.

There are no known Windows-like Viruses in the wild that self replicate and affect macOS, because of the underling UNIX  Foundation and Permission Limitation. 

The Operating System resides in a Sealed and Read Only Volume that cannot be opened by the User nor by Third Party Applications.

The Only thing this Antivirus software is protecting is the Bank Account of the Developers and for zero return to the User aside from the problems this software creates.

AntiVirus Developers purposefully Market their product to create a “ Fear Factor “. In so doing, creating a False Need for their Product.

Security. Built right in

Mac app security enhancements

 The Built in Security  is all that is required to protect the computer.

junaidjabbar wrote:

Here's how to remove a virus from a Mac:1.

How do you remove what doesn't exist?

In order to evaluate your system and it's health download and run Etrecheck. 

Copy the report

and use the Additional Text button to paste the report in your reply.

Then we can examine the report and see if we can determine the cause of the problem.

Here's how to remove a virus from a Mac:

1. Disconnect from the internet.
2. Reboot in safe mode.
3. View the Activity Monitor.
4. Uninstall recently added apps.
5. Run a virus scan.
6. Check your browser homepage and delete your cache.
7. Delete unwanted browser extensions.
8. Restore from a backup.