Yes, you can qualify for finacial aid for online colleges. The college will help you with it; tell you what forms to fill out, how to access them online, and who to submit them to. It was really when my husband applied for financial aid.
Each school charges different amounts. Some charge per course, some charge per term, and much of it depends on what classes you take. My husband has been taking college classes at Virginia College Online for 1 1/2 years and his student loans are $18,000. The total cost of his Associates Degree in Criminal Justce will be around $24,000. That's a lot less than many campus colleges.
The classes take about as much time as they would if you were going on campus, it's just that the hours are more flexible. They aren't really intense, but you can always start with just one or two classes to get the feel of things. My husband takes 3 classes each term and doesn't have any problems. The most intense time is the last week during final exams.
The most important thing is that the college needs to be accredited. If it is, then the classes can be transferred to another online college or to a campus based college. Decide what you want to earn a degree in, search colleges online to find one that you think you like, and contact them. It's easy after that. The colleges have people who you can talk to online or on the phone and they will answer all of your questions.
Good luck!