To get federal grants, loans, etc., students are required to file a FAFSA. Unless the student falls into one of the very narrow categories that would qualify them as independent (married, ward of the state, and a couple others), parents are required to submit THEIR financial information, as well as the student's. Aid awards are calculated with an expected parent contribution. No, parents aren't REQUIRED to pay, but that won't change what the student is awarded (i.e., if the parents don't contribute, don't expect the student to be eligible for more aid to make up the shortfall). If parents won't submit their financial data, there won't be any kind of federal aid awarded to dependent students.
It's very hard to pay for school all on your own. While it's nice to think that everyone will be eligible for substantial scholarships, grants, free tuition, etc., in reality, very few are. My DD graduated #3 in her HS class, with all the bells and whistles on her resume (leadership, volunteering, scores, etc) that you'd hope to see, and had AP credit for three college courses. Unfortunately, she only received about 50% of what she'd need in grant/scholarship money, wherever she applied. She didn't get the merit money she was qualified for at our state university because her guidance counselor didn't get her transcript in by the deadline- even though she and he got all the rest in. Somehow she slipped through the cracks (and yes, she was following up with the guidance counselor... sometimes, poop happens). We buckled down, she got some small scholarship money every year (either from her HS, my college class alumni group, her college or major, etc), took only subsidized loans. DH took on a second job as an adjunct at her school for most semesters, so in addition to the extra income, there was a 25% tuition waiver. He and I paid about $5K a year OOP for her schooling. DD worked hard at school, had an internship for the summer before senior year where she earned enough to pay her rent, gas, and "fun money" for senior year, and graduated summa cum laude. She owes about $26K in loans, which means we/she covered about two-thirds of her college costs, in one way or another, while she was in school. It was hard, financially, but we made it happen. We'll help her with the loan payments, too; it was something we decided to do when it became obvious that we weren't going to have any big-time college account for her.
And regarding unsubsidized loans... yes, they are available, but be prepared to start paying the interest on these loans the day that you sign them. Options are to start making payments the next month, defer payments and roll the interest due into the principle, or just pay the monthly interest and postpone paying the principle until after graduation. None are particularly attractive options, IMO.