If Christ is God...

If Christ is a God, why did God the Father needed to command us to worship Christ?

Nonmembers say "Why do you worship Christ if worship only refers to God? So it means you acknowledge Christ as God."

We worship Christ not because he is a God, but because God "exalted him to the highest place and gave him the name that is above every name" so that every knee should bow or in other words, everyone will worship Christ for the GLORY OF THE FATHER and not for the glory of Christ himself.

"Because of that obedience, God lifted him high and honored him far beyond anyone or anything, ever, so that all created beings in heaven and on earth—even those long ago dead and buried—will bow in worship before this Jesus Christ, and call out in praise that he is the Master of all, to the glorious honor of God the Father." Phil. 2:9-11 The message

"Therefore God exalted him to the highest place and gave him the name that is above every name, that at the name of Jesus every knee should bow, in heaven and on earth and under the earth, and every tongue acknowledge that Jesus Christ is Lord, to the glory of God the Father." Phil. 2:9-11 NIV

If Christ is a God, why did God the Father needed to make Jesus LORD and Christ? Did Christ cant do it by himself?

"The whole Jewish nation must know for sure that God has made this Jesus, both Lord and Christ. He is the One you nailed to a cross!” Acts 3:36
If the doctrine Trinity is correct saying trinity is co-equal with each other, why did our Lord Jesus Christ said "My father is greater than I am" and why will Christ be put UNDER God?

"As the Scriptures say, “God put everything under his control.” When it says that “everything” is put under him, it is clear that this does not include God himself. God is the one putting everything under Christ’s control. After everything has been put under Christ, then the Son himself will be put under God. God is the one who put everything under Christ. And Christ will be put under Godso that God will be the complete ruler over everything." I Cor. 27-28 

"You heard me say to you, 'I am going, but I am coming back to you.' If you loved me, you should be happy that I am going back to the Father, because he is greater than I am." John 14:28

If Christ acknowledge a God, while he himself is a God, then there will be two Gods, right?

"About the ninth hour Jesus cried out in a loud voice, "Eloi, Eloi, lama sabachthani?"--which means, "My God, my God, why have you forsaken me?" Mat. 27:46

"Jesus said to her, "Don't hold on to me, because I have not yet gone up to the Father. But go to my brothers and tell them, 'I am going back to my Father and your Father, to my God and your God.'" John 20:17

more here.