I can answer some of these.
1). Yes. You have to fill out FAFSA to get a Stafford loan. There is no hurry though if that’s all you’re interested in because loan money won’t run out. It’s the institutional aid that uses FAFSA that might be limited.
2.) No idea on this one.
3.) You can include up to 10 schools to have FAFSA info sent to. I’m not sure how you do more, delete some and add others maybe? But, the point is you can pick and choose what schools to send it to.
4.) Yes, some schools require you fill out FAFSA to be considered for merit aid. Best to just ask the individual schools.