I had a £2 Iceland pizza for my dinner and it was delish. I think they even deliver too so you could do a big shop and wean yourself off takeaways. Step at a time and all that.
They do those meal in a bag things too in iceland now - pasta, risotto, noodles... all sorts and you just put the amount you want straight in the pan an cook it.. x
Can you give yourself a limit? One a week or once every fortnight? Also think of something you really want, a new laptop? Holiday? Outfit? Etc and put the money you would have used on these takeaways into a little savings pot. Think of all the stuff you could get with that money that’s just going on food. Good luck!!