I recently got engaged to a man who my parents chose and for whom the Istikhara came out positive. I have spoken to him a few times, he is a good person but I don't really feel any connection with him and it worries me about the future. What should I do?
Bismihi ta'ala
A marriage should not be based on the answer of an Istikharah. You must decide on marrying the person based on a combination of things, from being religious, pious, high moral standards, good family, compatibility, shared ambitions, and so on.
What you should do in the situation you are in is find commonalities and work on the areas in which both of you connect. If he is a good person, and he has positive qualities, for sure things will work out for both of you. It is unrealistic for anyone to assume that we will share all similarities with our spouse, as there are always going to be things we differ on.
People change as well. You might not feel the connection because you were expecting something else, or had some image of an ideal spouse, or maybe you felt something else, but as you are married now, you are able to find ways in strengthening your bond with your husband.
With prayers for your success.