While he was still with them, he said: Don't leave Jerusalem yet. Wait here for the Father to give you the Holy Spirit, just as I told you he has promised to do.
As bad as you are, you still know how to give good gifts to your children. But your heavenly Father is even more ready to give the Holy Spirit to anyone who asks.
Jesus was talking about the Holy Spirit, who would be given to everyone that had faith in him. The Spirit had not yet been given to anyone, since Jesus had not yet been given his full glory.
Not everyone saw him. He was seen only by us, who ate and drank with him after he was raised from death. We were the ones God chose to tell others about him.
Jesus was taken up to sit at the right side of God, and he was given the Holy Spirit, just as the Father had promised. Jesus is also the one who has given the Spirit to us, and that is what you are now seeing and hearing.