I have a son in Y6 there. No, they don't have a kitchen so most people provide packed lunches. There is a delivery service from Pret a Manger that a few use.
It is mixed ability but there is some teaching in sets as the boys get older. In years 7 and 8 the two classes are split according to future school/scholarship applications. I've just applied for Kings, Hampton and St John's 13+, and my son is aiming for drama or music scholarships. Other popular choices are Epsom, Reeds, Emmanuel, Whitgift, Trinity... A fair few boys get scholarships of some sort and one got the top academic scholarship to Kings last year, a very impressive achievement.
He isn't interested in sport, so I don't know much about what the A teams do but there always seems to be some tournament or other going on. I think the new thing is to start a competitive swim squad. In Y6 this term he has to do football twice a week, swimming once and climbing once. It will be rugby next term and cricket in the summer.