Soft food is anything you can mash with a fork. I ate things like fish in sauce with mash, scrambled egg and beans, mashed up roast dinner, tuna with mash, shepards pie, fish pie, the insides of jacket potato with beans or cheese. Basically try anything you can mash easily.
As for crackers, I started with wholemeal Melba toasts and ryvita. I used to put smooth peanut butter on them, which is a good source of protein.