Is it allowed to make dua in my prayers for the name of the girl I want to marry.

Du'aa is the essence of Ibaadat. We are encouraged to make Du'aa for all our
needs. It is also encouraged to make Du'aa for others.

Du'aa is also a means of ones spiritual upliftment. If you are already
proposed to the girl and is certain to marry her and your making Du'aa for
her is not just motivated by your passion for the girl, then you may make Du
'aa for her. If you are not proposed to the girl and you are motivated by
your passion for the girl, then that is a shortcoming and detrimental to
your spirituality. In such a situation, you should not think or make Du'aa
for the girl.

and Allah Ta'ala Knows Best

Mufti Ebrahim Desai