Do we have a plan to incorporate the Bengali language in Duolingo in future?
Sadly the Bengali course is still not in the incubator... Together with Urdu, they're the two most spoken languages not yet added on Duolingo. (source: https://en.wikipedia.org/wiki/List_of_languages_by_total_number_of_speakers#Ethnologue_(2020,_23rd_edition) )
I hope so! I'd love to learn Bengali. After all, it is one of the most widely spoken languages in the world. Maybe we'll see an incubator team soon :)
Edit: There is an incubator page up, so at least there are plans for it sometime! http://incubator.duolingo.com/courses/en/bn/status