If I married someone in Pennsylvanian who is 16 could I collect welfare if I came from Canada and I was 19 and I rented some place or something?
...you have no idea how hard it is to get on welfare in the US, do you?
You'd basically need to be on disability, which takes 2 years on average. You have to prove that you can't work in literally any job, and have at least one doctor backing you up on that.
It's not gonna happen.
Well you sure can't live off of what most people think of as welfare, Temporary Assistance for Needy Families (TANF).
Disability pays $4,000 less than the poverty limit per year but it's a lot easier just to get a damned job if you can.