How can I check if my iPhone has a virus?

Unless you "jailbreak" your iPhone there are no viruses in public circulation for iOS, so there's no need.

hi my phone was hot, apps crashing, people were sending & receiving messages with my apple ID, battery wasnt lasting. heres what fixed this for me. go to settings, apple ID, scroll down to see what devices show & remove any that arent yours. for me, there was a device labeled roku that was showing & even though i have a roku tv, it turns out that wasnt my actual tv.. someone had gained access to my icloud & was hiding under a legitimate looking device name. after i removed it, phone stopped with “virus/hacking” type issues. after removing change icloud password & i even changed my passcode. hope this helps u too

Most likely a scam message to get your ID and passcode. As noted, an iPhone cannot get a virus.

It's a scam to scare the user into giving info or money. And they can get viruses, but they're extremely rare.

If you have to ask what one is, you haven't done it, so you need not worry about viruses on your iPhone.

I got a message that I have a virus on my iPhone.