My 2 month old baby has this "habit" of drinking bit by bit... Be it either formula or breast milk... Isit normal? And also is this "habit" to be worried about?

You may wish to check if it's colic. Colic may cause baby to geel uncomfortable during feeding and nake them drinks very small quantity each time. They are too young to tell you but as mothers, we should be able to tell. Monitor baby for a while and uf tou think that it's something that you are concern about, pls seek assistance.

Could it be the teat is not suitable for your baby? Because the texture is different for every brand. My son takes pigeon well, but for medela or avent he rejects or when he's very hungry he will take in bit by bit but not want it fully. Could be the teat. Try changing to different brands.

How long is the feeding interval? For newborn normally need to be fed every 3 hours and if feed less than this interval baby have not digested the milk yet and thus take in less milk. Try to find out the reasons baby cries instead of offering milk each time.

when my bb stops half way, I will burp her first before continue with the balance and she will finish it quietly. no fuss. or maybe is the teats issue or she don't like the formula?

Read up on cluster feeding and growth spurts where babies can and would cry for milk almost every hour.

What do you mean drinking bit by bit