I usually start my babies on soft food when they are about 4 wks old, but they continue to nurse their momma until 8 wks. By that time I try to have them eating both hard crunchy food and some canned food along.
I usually start mine at about 5to 6 weeks old i give them baby rice cereal mixed with Esbilac goats milk in a can and i put a few drops of those nutra drops in it with some honey they love this. then eventualy i add cottage cheese and cesar soft food and i leave the hard food in there all the time with water for them to pick at
As a general rule I let my dams decide when the puppy is old enough to wean, however I start to give them baby rice cereal around five weeks old by eight weeks I am letting the try a few pieces of kibble.