Confused about applying for FAFSA?

I always thought you were supposed to apply for FAFSA after sending your college application.
But apparently FAFSA is supposed to be filled out at the latest March 1st of every year.

I’ll be applying for college in the Fall of this year.

So…is it too late to apply for financial aid now?
And what does that mean? I’ll be paying full tuition my freshman year?

I didn’t even know! No one at school (teachers) have said anything about FAFSA deadlines and my parents don’t know anything about college because they’re 60 and still think tuition is $6,000 a year.

Should I still try to apply? I don’t even know if I should be worrying about it right now?!