A non-permanent resident alien is an individual that holds employment in the United States. They are not a citizen and they do not have a green card.

"My aunt became a legal permanent resident of the United States after receiving her green card."

In Canada, a PR card is a permanent resident card. A PR card is what is used for official proof of being a permanent Canadian resident.

Yes, they do. The Canadian permanent resident card is the only proof of identification that proves, both inside and outside of Canada, you are a permanent resident of Canada.

You need to have a valid permanent resident status if you want to move to the United States.

If you have a college degree you can try to find a sponsor that will help you file for a H1B working visa and then eventually apply for a permanent visa and naturalization.

Or, if you are eligible, you can enter the Diversity Visa Lottery Program, also known as the Green Card Lottery. ~90,000 out of millions of applicants are randomly selected each year, and 55,000 out of those eligible winners get a United States Permanent Resident Card (Green Card).