I dedicated myself to Jehovah four years earlier (I have anxiety problems so I didn't get baptized right away) but if I want to be a Christian do I need to dedicate my life to God and Christ? I'm not sure.
You must be born again. That is what Jesus told Nicodemus.
When you get born again you get a new spirit... and a new destiny.
Romans 8
1 There is therefore now no condemnation to them which are in Christ Jesus, who walk not after the flesh, but after the Spirit.
7 Because the carnal mind is enmity against God: for it is not subject to the law of God, neither indeed can be.
8 So then they that are in the flesh cannot please God.
9 But ye are not in the flesh, but in the Spirit, if so be that the Spirit of God dwell in you. Now if any man have not the Spirit of Christ, he is none of his.
14 For as many as are led by the Spirit of God, they are the sons of God.
16 The Spirit itself beareth witness with our spirit, that we are the children of God:
28 And we know that all things work together for good to them that love God, to them who are the called according to his purpose.
32 He that spared not his own Son, but delivered him up for us all, how shall he not with him also freely give us all things?
35 Who shall separate us from the love of Christ? shall tribulation, or distress, or persecution, or famine, or nakedness, or peril, or sword?
36 As it is written, For thy sake we are killed all the day long; we are accounted as sheep for the slaughter.
37 Nay, in all these things we are more than conquerors through him that loved us.
38 For I am persuaded, that neither death, nor life, nor angels, nor principalities, nor powers, nor things present, nor things to come,
39 Nor height, nor depth, nor any other creature, shall be able to separate us from the love of God, which is in Christ Jesus our Lord.