The Bible says to desire to prophesy; that is calling. It says "you all may prophesy"; that is qualification. Do all prophesy? No, know many are called and few answer the call.
1 Corinthians 14
"3 But one who prophesies strengthens others, encourages them, and comforts them. 4 A person who speaks in tongues is strengthened personally, but one who speaks a word of prophecy strengthens the entire church.
5 I wish you could all speak in tongues, but even more I wish you could all prophesy."
No, everyone is not given the gift of prophecy. Paul is saying in this section that each Christian is given a gift in the Holy Spirit and everyone does not have the same gift.
Paul is praying and urging everyone else to pray for the gift of prophecy so the church will be edified.