We know God through its impact, we did not see dark matter or consciousness for e,g yet we believe it exist because of its impact ; same we know God through its attributes; another way of knowing is through Gods Prophet ( like through history) their character, morality and teaching ; one more way is to look inside at our own self ( not the material self)

tried to explain here how a monotheist religion will leave this world in a better spot and how it could be used as a way to proof God existence

https://medium.com/illumination/monotheism-the-religion-of-all-prophets-5718c20ad0c1

Do not want to put any trouble in your Christian faith; but have you considered possibility of Jesus as a Prophet rather than a Son ( or God himslef)

https://mfakhar2000.medium.com/jesus-was-none-but-a-prophet-b26aea21247e