The Indians trying to make everything about India are already here. Let me give you some short answers to your questions:
1. Bangladesh doesn't need India to "give it some frigates". Bangladesh has recently agreed with China for building warships at Bangladesh with the Chinese overseeing the projects and supplying equipments and weapons. Right now we are just building corvettes and missile boats but if needed we will build frigates.
2. India itself doesn't produce all its equipments and relies on other nations for such. And one of them is Israel, which is a big problem for Bangladesh.
3. India isn't that rich that it can just give away things like frigates.
See how bright the sky is lit. That's your submarine burning.
Our stupid stooge of a government will only look to gain from military deals since they are done with a level of secrecy. We should have added a at least a few Song Class submarines and bought some Su-35 for deep sea strike ability. Right now, any nation can go unchallenged at the deep of Bay of Bengal.