white curd like substance is quite natural by infants till 10 months. Reason may be either they are overfilled or the milk is not digested. Dont worry about that. But keep burping your baby after every feed.
Cerelac , vegetables , mashed potatoes you can start giving from 5th months onwards. But Rice ,only after 6-7 months. Because it might not digest properly for 6 months below babies. Give mashed rice with Moong dal and ghee which is very good for their health. Give your baby ragi,cerelac, banana, vegetables,milk now these are more healthy for them.
I have a 2.10 yr old girl baby. But am not a doctor.