How do I stop virus pop-ups and prevent iCloud account expiration?

I have noticed on Adult websites and gambling sites, there are popups, telling you that your iPhone is “infected” and your iCloud is “expired”. Don’t believe these things. Keep your iPhone Software up to date from Settings app & stop going to websites that show you this. Also keep your 3rd party software on your iPhone up to date.

As there are no viruses that affect iPhones and your iCloud account will only end if you stop paying for it, all such messages are scams.

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

If you get a notice of a "virus infection" out of the blue, that's a scam message. Same for messages claiming that your iCloud is being "hacked".

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

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

• iCloud accounts never expire
• iPhones don’t get viruses, and never have

All such notices are scams to steal your money or your identity.