When you are afraid, train yourself to ask where that fear is coming from. Is it because of a past experience, or just because it’s unknown. We are supposed to learn from past experiences- like, don’t touch something hot or else you could get burned. We learn to use the proper tools or safety equipment in order to handle the hot thing so we don’t have to be afraid anymore.
What are you afraid of? What fear gets to you? How do you handle it? You have to use faith to fight against fear. Faith in God, not on your own abilities. You must know the truth of God’s word, too, because the devil is a liar and will whisper fear to you every chance he gets. Make sure you listen to the Spirit of God who is with you!
God doesn’t not want us to be afraid. Period. He says so over and over in the Bible. However, it also says that the fear of the Lord is the beginning of wisdom - this is speaking more of reverence and awe than cowering in fear. The devil is afraid of God, though - as he should be.