Do you know what else you can and cannot do? Though some laws vary by state, here's a list of things that you can and cannot do when you enter adulthood. These are just a handful of the cool things you can do once you hit When you hit 18, you're legally allowed to drive an ice cream truck. Checklist of teenagers' legal rights at age Things an 18 -year-old still can 't do legally And as parents of an 18 year old you need to remember to check. It's THE milestone you 've been waiting for all your young life. Turning 18 is that long-awaited time when you become legal and can do all the things you once. Learn about the interesting things you can do once you turn 18 and start to do stuff that was kept away from you because of the legal issues. Most of the time you don't feel any different after birthdays because nothing really changes, but it doesn't stay that way since there are many new and exciting.