How can I make my faith strong enough?

It’s been two years since I am a member of our church, but I don’t understand the teaching of our leader, sometimes I doubt my faith in this church, and there are times that I want to change my religion. I feel like I haven’t learned anything, I want to know how I can solve these problems. But how?
How can I make my faith strong enough? How can I not doubt my religion?

Your faith is in Christ, not your church or a particular leader. When disappointed in your church or your leader, pray for guidance. Proceed with caution and know there is no perfect church or leader. Deepening your faith depends mostly on you keeping your eyes and mind on Christ alone, not your leader or your church.

"Looking unto Jesus the author and finisher of our faith " Hebrews 12:2 KJV
"For as many as are led by the Spirit of God, they are the sons of God ". Romans 8:14 KJV
The first thing is, are you saved. Have you accepted the Lord Jesus as Your Lord and personal Saviour i.e. are you born again? If No, then you need to first be saved so that you can have a personal relationship with God.
If you are already saved, then you need to always look unto Jesus and not to people. You must allow the Holy Spirit to direct you totally.
There is no perfect church. If you leave one, where you are going, you will see something which you are not pleased with there also. We are called to have a personal relationship with God. So, build a personal relationship with God through the leading of the Holy Spirit. Do not quit Christianity. May the Holy Spirit build you by Himself.