The common question: Where is the proof? Well, loving God and following/serving Him is mainly about faith, but for the proof, we have (1) His word, The Bible. (2) The entire Earth, Universe, and everything beyond those reaches.
In John 14:10, Jesus says: "Do you not believe that I am in the Father, and the Father is in Me? The words that I say to you I do not speak on My own initiative, but the Father abiding in Me does His works."
The Bible provides a way for God to speak to us all on a daily basis. Reading it is just opening a door for God to show us what He wants in our lives.
There are also the many people who follow God and have strong faith in Him. God can often take the opportunity to work through His followers, whether it be speaking, writing, or anything else. Anything is possible through God.
Genesis 1:1 says: "In the beginning God created the heavens and the earth."
It's as simple as that. God created everything! Just looking around and you can't help but notice God's existence. A sunset, or a rainbow. These could only be made by an omnipotent, peaceful, and gentle God. The God. Also, with the idea of evolution, the world being created on a coincidence is more illogical than some would say the idea of God is.
God made the world, through creation, through His splendor. He made every minute detail according to His plan. The idea that the perfect combination of gases to create what was necessary for human life just occurred, well that is nonsense. God knew what He was doing, and He did it for a purpose. Basing the relationship with God on faith, and this entire world, it could only be God who exists and created the world.
