Alert on my phone telling me it has been infected and I have 1 minute to down load malware to clear it

Assuming this is via a web site: close the offending page and avoid sites that are involved in such bogus advertising tactics. All such messages are scams from criminals 100% of the time. Never, never, never download anything based on a popup message.

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

It’s a scam sent by criminals. Ignore it. Click here for more info→Recognize and avoid phishing messages, phony support calls, and other scams - Apple Support

A scam. Delete it.