Before, i used to not believe in God, but then miracles happened and if you're still doubtful about him, please take some time to read this

1, Watch miracle videos in youtube. watch documentaries where they encounter miracles.
2. Listen to worship songs. when i first heard it, i felt goosebumps all over my body, i even reflect my self during that time.
3. Read bible
4. Read quotes about him
5. Pray, it is the most important thing