It’s great that you want to believe in God. It might be helpful if I explain what it means to be a Christian. There’s not really any measure of half or full Christian because being a Christian means having a restored relationship with God.
By default we are seperated from God. The only relationship we have is us rejecting him and therefore being alienated from him. That relationship can be fixed though when you know and trust that God came into the world as a man, Jesus. Being a Christian involves believing that Jesus gave his life as a sacrifice to take the punishment our rejection of God earns us. And also believing that God raised Jesus to life again.
The way to get to know God then and see that he is really there, is to get to know Jesus. The way we know Jesus is to read the biographies of him in the Bible. One of the best is by Luke. Luke wrote his account of Jesus’ life so that the man he wrote it to would have certainty of all that Jesus did and said.
Be reassured that God does wants you to believe in him. Jesus told the story of the lost son which is in chapter 15 of Luke’s book. It’s all about God wanting people to come back into a relationship with him. In that chapter Jesus says “there is rejoicing in the presence of the angels of God over one sinner who repents.”
The most important thing you can do is to speak to God and ask that he would help you to believe in him. The Bible promises us that God hears and answers our prayers. There’s no special way to pray, it’s just a conversation in your head or out loud.
It might also be helpful to come back with some more questions. Are there any specific things you don’t believe about God?