Posted: 17/05/2014 at 07:55
Hi Pili Pala
Lots of information on this link http://www.saga.co.uk/lifestyle/gardening/plant-portrait/how-to-grow-brassicas.aspx about winter veg including some suggestions for varieties.
This link http://www.rhs.org.uk/advice/grow-your-own/vegetables/lettuce has the basics for growing lettuce, again with some suggestions for varieties. I would also suggest some of the 'cut and come again' types of salad leaf mixes.
To start with I suggest you go to a local garden centre and select your seeds - they'll have loads of choice and the seed packets will also have basic instructions on them.
Then as you get more experienced and perhaps want to try some more unusual varieties you can order seeds from some of the specialist suppliers.
Good luck and don't hesitate to come back and ask us any questions you have