Welcome to Justanswer.com, my name is Dustin.
I'm sorry to hear about the issue you are having, I will do my best to help you resolve it.
Please do not enter any passwords or info in the virus popup. The password ***** info you did enter, that wasnt for your icloud or apple id was it?
We need to t ry and remove the problem. Shut down the computer, hold power if neccesary.
Then, start the computer and hold down the left SHIFt key as soon as you press power to start the mac. This will start you in safe mode.
Once you are in safe mode. Follow these steps to remove the v irus. ( or , I can connect and remove it for you )
If you get stuck or run into any issues, let me know.
I strive to provide great service, and greatly appreciate a 5 star rating clicked and submitted when you are satisfied.. I always answer follow up questions.
Senior Technician and Network Switching Systems Operator / Maintainer.