1. Yes There Is A God Because All Of Nature Speaks Of Him.
Your question whether there is a God, shows that you are thinking about this important matter. It is a question that makes sense and to which God has a very clear answer. He says just to look around you for a moment and ask yourself where does all this come from?
Could the sun, the moon, or the stars have created themselves? Or do you know someone who could make even just one little star? When you look at a woman sweeping the yard with a small self-made broom, you will not be impressed by the broom and will say to yourself that you could also have made one but, when you look at a huge aircraft crossing over above you in the sky, you would immediately admit that a very clever person with huge resources must have made it. Take a handful of sand and think of it that not even the most intellectual scientist can make even a single grain of sand out of nothing. Yes, the works of God are immense and if we honestly look around, we must acknowledge that truly there is a God and therefore He says in his Word:
For the wrath of God is revealed from Heaven against all ungodliness and unrighteousness of men, who suppress the truth in unrighteousness, because the thing which may be known of God is clearly revealed within them, for God revealed it to them. For the unseen things of Him from the creation of the world are clearly seen, being realized by the things that are made, even His eternal power and Godhead, for them to be without excuse. (Rom 1:18-20)
So, God says that He revealed himself to man in nature, but that man willfully ignores and suppresses that knowledge because He does not want to serve God.
The ox knows his owner, and the ass his master’s crib; but Israel does not know; My people do not understand. (Isa 1:3).
Yes, an ignorant animal knows very well to whom he belongs, who cares for him and who he must obey, but the clever human being pretends not to know Who made him, Who causes his sun to warm him and provides the air which he breathes.
2. There Is A God Because He Becomes Visible To Man Through The Bible
The Bible contains all the information which man needs to get to know God and to walk with Him.
All Scripture is God-breathed, and is profitable for doctrine, for reproof, for correction, for instruction in righteousness, that the man of God may be perfected. (2 Tim 3:16,17).
3. There Is A God Because He Reveals Himself To Man By His Spirit.
Please read Prov 1:20-33. The Holy Spirit, here called “Wisdom” is continually engaged in speaking to man, but people do not recognize that inner voice as the voice of God.
Once a person gives his life to the Lord so that He can live within him, the Holy Spirit testifies to his spirit that he now is a child of God (Rom 8:16).