Does my baby sleep too much? And other ftm questions!

Hiya! Hope everyone is well

I'm slightly concerned about my babys sleep. He's 6 month old but was prem so is 4 months corrected, and honestly since we got him home he's been amazing fantastic sleeper. He sleeps through the night for about 8 to 10 hours straight, and had quite a few naps during the day as well. We are trying to get him into a better schedule, as he usually has his last feed at about 1am and wakes up at about 10am, so I'm trying to bring that forward gradually.

What I'm concerned about is that he tends to have like 4 or 5 naps during the day as well. He wakes up every 2 hours for a feed and has 6 feeds a day. I'm worried he's spending too much time lying down, I'm a ftm and our outreach visitor from the hospital stopped coming about a month ago, where we were having weekly visits, so I'm feeling a little lost.

Also is he drinking enough? He has between 800ml and 900ml of nutriprem formula a day. When do I give him different formula? He gets a prescription for his nutriprem but no one told me when to stop that and use regular formula?

Sorry in advance if these questions seem stupid, I'm feeling a little lost and alone. Tia