what does mean "rokinat.co.in"

Sounds like a scam – perhaps one presented in the form of a Web notification? (No remote site would know if there were viruses on your computer unless you had actively run a scan.)

Recognize and avoid social engineering schemes including phishing messages, phony support calls, and other scams - Apple Support

If the message is appearing in the upper-right-hand corner of the screen, here's how to block it, and others like it, in Safari. (The idea would be the same for other browsers, though the exact controls might be different.)

Stop Unwanted Notifications – Apple Community

The "rokinat.co.in" may be the address of a Web site – if that is the actual name and not a name used to disguise a link that goes elsewhere. The ".in" domain is the top-level domain for the country of India – so this site appears to be one registered in India (although that doesn't necessarily prove that it's for a local company).

When I did a Google search for "rokinat.co.in", search results came up that would make me want to avoid that Web site like the plague.