my baby boy is 1month 1week old his birth weight is 3.4 and now he is 4kg. there are 6 to 7 wet diapers daily and poops 1time. is this good or should I start formula,,?

A. A child should gain at least 500 g in a month so if you look at it your child is gaining good weight gain your child is 600 g plus the birth weight so this is good enough over or I can tell you the growth of your child is just going as per the expectation