We can see clearly the proves of God's existence in the order, beauty and purpose in creation, His existence cannot be proven in a lab or classroom.
We see in Psalm 19:1 tha everythings on earth including the change in seasons, rising and setting of the sun and how the seeds planted bear fruit, all these things are His works.
The reflection of God is seen in the very being of man and everything that surrounds him.
The longing in our heart to worship, justice and love points to a supreme being.
In the Bible, when people who had no hope met God, their lives were transformed to one with purpose.
Love, conscience and faith can not be eexplained by science.
When we observe God's creation and we feel His influence in our heart, these things are a testimony of His existence.