Hi Josaphine,
Please think very carefully and read up on the pros and cons of wing-clipping before making any decisions on this. Many folk think it is cruel. Other folk think it's the right thing to do.
My own experience of it is this - My OH and I have rescued many birds over the years. One particular bird had been clipped by an inexperienced person. The bird very nearly bled to death, he came to us very traumatised and it took us a long, long time to bring him back to normal. The vet who treated him advised that he be put to sleep - I wanted to give him a go, as I have treated depressed birds before, with success.
Some would argue that the bird is safer if clipped, for example, it can't fly far, or sometimes not at all, without falling to the floor, and therefore would be unlikely to fly into a window or onto an open fire. (I have known of budgies doing both, btw).
Others would argue that it is cruel to deny a bird its natural instincts. It's a difficult debate. Personally I would never clip, although I am sure there will be ABers who feel differently.
Re the lettuce, I have always given all our budgies and cockatiels lettuce, they seem to enjoy it, although I am told there is little nutritional value in it for them. I also give them spinach and pea-pods, which they love.
Best of luck with your new little friend.
chappie.
xx