for marriage i do have 2 choices both r nice for whom should i do istikhara first ??can I supplicate O'Allah pls bless me a husband from them who's best for me both n dunya n akhirah??pls do guide me what to do n pray for me as well.jazakAllah

All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger.

It is better for you to choose the one who is more religious and better in moral conduct, and seek the advice of the trustworthy and experienced people. Once you would have chosen one of them, you should perform the Istikhaarah prayer (regarding marrying him) while putting the matter in the Hands of Allaah to choose for you what is best. For more benefit, please refer to Fatwa 81434.

Also, it is permissible to supplicate with the supplication that you mentioned in the question.

Allaah Knows best.