I thought ds1 was pretty self sufficient and independent in yr6, but I was rather amazed how much input from me he needed in the first few weeks of secondary.
Seriously, my top tip to parents is to plan to have as much free time after school as possible in the first few weeks.
Every night we chatted about his day, talked about the school routines and issues that had come up; checked what homework had come in and how it was recorded, helped him organise his resources and school materials at home, talked about issues surrounding lunches, breaks, PE lessons, bus-catching, handling cash, managing a damp coat on wet days, etc etc etc.
You might think this was over the top, but it was really necessary: there's a lot to take in at secondary and if children are not organised, it's a real barrier to learning.
It definitely paid off, as once we were through those first few weeks, he was great and just got on with it himself with the routines and systems that we put in place. He never forgot PE kit, never forgot homework, etc. We've been pretty hands-off ever since and he's in yr13 now!