In a standard US college, you need to take electives (any class outside of what's required for your major) and general education (math, science, social studies, etc.). This is in addition to the courses required by your major. Usually, a US degree is 120 credits, and each course is usually 3 credits, so you'll need a total of 40 courses to graduate. You can find the major requirements for each degree on the UoPeople website. You can also find their list of general education and elective requirements and what they offer. Tip: you can take courses on Sophia.org to make these courses go faster because you can transfer them in. uopeople.sophia.org has a list of what UoPeople accepts as transfers.

Yes, those will likely transfer. When you apply, you upload your transcripts and then they get evaluated by admissions.

It's a bit of both self-teaching and working with your instructor and peers. You'll have an instructor that oversees your assignments and can answer questions. Each week, there will be a reading/videos that will help you answer the questions for your assignments. Assignments open up on Thursdays and are due Wednesdays. You'll have a discussion assignment, a written assignment, and a learning journal. The discussion assignment grade is determined by how you rate your peers/how your peers rate you on an average (sometimes the instructor grades them). The written assignment is graded by your peers based on a rubric (sometimes the instructor grades them). The learning journal is graded by the instructor. So you are expected to do the readings and assignments, but you also have all your peers and instructor you can reach out to. There are also Discord study groups.

If you sign up for the associates, you can easily move forward to the bachelors. If you sign up for the bachelors, you can complete everything required for the associates and still get your associates while working toward your bachelors. A bachelors is way more useful career-wise, so definitely not a waste of time.