Virus on iPhone 13

Hi

i know if already asked about this before, but I’m super confused.

I was watching some videos on my phone tonight and a message popped up saying my phone was infected with 37 viruses. I quickly closed it and began my Google search on iPhone viruses, many of you in here say you can’t get viruses on iPhones is that true?

should I do something or just watch out for anything weird

would appreciate any help - thanks in advance