I think you should not put all your eggs into this one basket......Because very likely you two are not on the same page,   (unless confirmed by him) he just started his dating life and you already want to settle down.

If i were you, I will still continue to seek potential "candidates" (since your goal is to get married)

And if the topic of "Exclusive dating" is brought up, you can start asking the question of " where do you see our relationship end up in 2 years" etc.