Can he propose to a woman whom his friend saw before and decided not to marry?

No File Exists
Check below answers in case you are looking for other related questions:
Will getting married to someone who is possessed affect the children in the future?
He loves his fiancée but she wants to cancel the engagement; what should he do?

No File Exists
Related Answers:
Can he marry the daughter of his mother’s paternal uncle?
Her fiancé refuses to let her wear hijab
She is refusing those who propose marriage – could it be sihr (witchcraft)?
Will getting married to someone who is possessed affect the children in the future?
He loves his fiancée but she wants to cancel the engagement; what should he do?

Recommended answers for you:
The virtues of pregnancy
Ruling on keeping pictures and children’s toys
Ruling on using materials to which “animal glycerine” has been added
Are the five daily prayers mentioned in the Qur'aan?
Ruling on photographs