Answer :
He is a a man that is deeply connected to his African heritage. He also helps Beneatha discover her heritage, by giving her gifts like traditional Nigerian robes.
I don’t really know for sure but this is what my friend said is Joseph is An African student, Joseph Asagai courts the attentions of Beneatha. In trying to win her affections, he is persistent but never overbearing . Joseph is a fictional charter in the movie a raisin in the sun.Hopes this helps this is all my friend knows because I know nothing about this but my friend knew a little bit.