Is it normal that there are fake websites with viruses
Welcome to the Internet.
Trust no one, just because they exist or have a website or host something on a website or have written something on a website. If you can do it, so can criminals.
And creating a fake site or uploading malicous things is trivial. Not so trivial is creating a fake domain. You can complain to the service provider that hosts the fake domain. But be careful to actually complain to the underlying provider and not to the criminals.
For malicous things hosted on a legit platform, you can complain to the platform.
So yeah, unfortunately, it is common to see fake websites. Anything that people visit a lot is an attractive thing to fake.
For Itch there is another problem. There are scraper platforms. They copy the Itch catalogue right down to downloadable files. The scam might be software piracy or distributing malware. And funnily enough, I once found actual malware on Itch that was still indexed on such a scraper site.
Anyway, there is actual fake games with viruses in it hosted on the real Itch. Trust no one just because they exist on a website ;-)