Please explain the 'the gifts of knowledge' and if it is okay to allow who has this goft to pray over you and give you the message he receives.
The gifts of knowledge is not a gift for scientific civil studies of mathematics, or languages, or any other subject. It is only "to know" , i.e., to understand better the Word of God and its implication in our present life.It is a gift that is linked with anothr gift, the gift of Wisdom. Anybody can pray over you or over me or over any other person. But, we should be very skiptical about "the message they receive". Many times the Holy Spirit has nothing to do with that the person seems or assumes to receive from him. Even though the the Holy Spirit can speak to somebody in many ways, even by private inspiration, the Holy Spirit normally conveys his messages through the Church (by Word of God, through the Sacraments, Liturgy, and prayer).When somebody tells you that his message comes from the Holy Spirit, please don't readily believe it.A discernment of the spirit is always necessary in these cases. [ See CCC 2690]