How to remove virus from iPhone 8?

Google would not tell you if your iPhone was infected (they have no way of knowing). It sounds like a website, text, or email pretending to be google was trying to trick you into downloading something. Always be suspicious of messages claiming to be from companies such as Apple, Google, Samsung, etc.

Your iPhone is probably not infected.

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

Manaus1 wrote:

I received a message from Google telling me my phone is infected,

That is a scam. Delete the message. Do not download any apps that the message tells you to download.

Unless you have jailbroken your iPhone, it is not infected.

Unless you have jailbroken your phone, it doesn't have a virus. What makes you think it does?