To the people of Reddit that literally changed your identity. How did you do it ( instructions pls )

When I finally move out ( in 4 - 5 years or more ) I want a fresh clean slate. But in this age and time it seems very hard to change your identity. So I want to figure out how to do it. I don't mean in like a identity shift I mean literally just change my identity. Like I want to keep my name. I can change my age or just change the whole thing. but I'm talking like I need a new id, social security number, to birth certificate, all that. If you know how to please talk to me about it.