Help for a total beginner trying to grow veg on a roof terrace please.

[ALMummy]

I dont have a garden but am planting in pots out on my roof terrace.

I have planted tomatoes - they are still indoors and coming up nicely. When can I move these outdoors and will they do better in Gro bags or pots please?
various herbs also still indoors and also coming up really well. When can I move these into pots and outdoors?
Dwarf carrots - in pots out doors with absolutely no sign of anything coming up. I planted them about three weeks ago. Should I just give up on them because everything else I planted has shoots now?

Also any other recommendations would be welcome. I am leaning towards growing veg so if anyone could tell me what does well in pots and any other information at all I would be grateful. My Mum keeps talking about nipping out the tomatoes and I havent a clue what she is on about . Many thanks.

I grow tomatoes in growbags because I am too lazy and stingy to get pots. They do perfectly well, but remember you will have to stake them.
Nipping out the tomatoes means pinching out the top bud from the main stem, so that it branches out (thus producing more floweres and more tomatoes).

I dont plant a lot from seed, I prefer to get plants from a nursery. Courgettes are very easy to grow in grobags and give a good harvest.
I want to try runner beans this year, but cant find any so far. They grow fine in bags, but do need a lot of watering.

I would move the seedlings into pots when they get a few leaves, and start looking a bit cramped.

Yr Muum is probably referring to nipping out sideshoots. Imagine the upward shoot, then the branches off at right angles - side shoots appear pointing at 45 degrees up wards between the two. These are traditionally nipped out as they are a waste of energy for the fruiting side branches. Only nip the top shoot when you have got the plant reasonably high with plenty of fruiting side branches.
Runner beans are straightforward. Soak overnight, then put 2 or 3 in a pot, they'll come up very quickly. It's a good time to sort these out now.

Right, here goes......

Due to the price of veg/food going up, I would like to start a veg garden. We have a south facing garden which should be ideal but the soil is very solid and clay like and has only ever had turf on it for the last ten years since the house was built so there is probably a lot of builders rubble buried under the grass.

Where do I start? I have never gardened before. Is there an idiots guide book that I could buy? Or should I just forget the whole idea.

Any advice gratefully received.

Sorry! Ignore that message. I meant to start a new thread.