They don't recommend adding it to their bottles. But I did at 3 weeks because my LO had acid reflex and my doctor said it was ok as long as I didn't do it all the time.
I was always told, and it says on the rice box, not to add the rice to bottles. At about two months I started to feed my baby rice cereal with a spoon and I would add a taste of banana 1st foods. He loved it. I gave it to him about twice a day.
I started letting him taste it (via spoon) at 6 weeks old, but he wasn't a fan. I started putting it just in his night time bottle at 2 months and he was fine with it. Doctor told me to at 2 months, also.