I built raised beds and grew vegetables for the first time this year and
have run into the unknown. I'd be grateful for some help on...

Onions: I sowed seeds directly into the ground and not many germinated
so I filled in with sets. They've done well, I think, but I don't know
when to lift them, or do they stay in the ground toll needed? Some have
fallen leaves yellowing at the tips but some, the largest, are still
upright and green. Do they go to seed if left too long?

And wrt the sown ones, should these be lifted and used as sets next
year? Is that how it's done? Any tips?

Sweet Corn: I tried some of this but it hasn't been a brilliant year.
Still, most have at least one ear forming. Will they come to anything,
or is it too late? If there's any chance of getting an ear or two,
should I restrict each stalk to one ear?

Leeks: I bought a tray of seedlings and my 1940s book says to prick them
out into a larger pot or container and then plant them out when they get
as thick as a pencil. Once pricked out, though, they barely grew at all.
Eventually I planted them out and they have grown, though they're still
not at the pencil stage. Will they survive the winter and carry on next
year, or are they a lost cause?

Cherry Tomatoes: in pots. Trusses have formed and are gradually ripening
and there are still many flowers. Should I take what I've got (not a
whole lot) and pinch off the flower stalks now, or can I let them do
their thing?

A succession of early peas have finished now (I started quite late in
the Spring) and I wonder what can be sown/planted now in terms of winter
plants --cabbages or something of that kind?
I have both dwarf and climbing French beans, how long do they go on
producing, and same question about what to follow them with?

I welcome any advice or suggestions.

Brian Mitchell