Been through this stage with both of my two.
My advice would be, make sure their bag is suitable for secondary, nothing babyish, as you will soon be replacing it for the more grown up version.
My two hated the school food, said it was rubbish, so packed lunches.
Secondary schools often do equipment checks and detentions issued if you haven’t got the right equipment, ie number of pens, pencils etc.
Much more PE kit required, ie rugby boots, dance wear etc. Uniform is strictly monitored.
Be prepared for much less contact with school, everything is directed to the student.
Year 7 is very heavy on homework.