>>482753That's a good question.
You could have a friend register a website for you in their name. That would work, and it would be more anonymous than registering it yourself. I think there are ways to technically register websites anonymously, too, but that seems to be pretty rare, and I'm not sure how.
With instagram… you could use a friend's phone or perhaps get a burner phone without your name on it. It's been a bit since I've bought a phone, I'm not sure how you'd do that. It does really suck that many big social media sites, like instagram, require that sort of info, now. I remember when none of them did. It's kinda classist, frankly.