"Hear O Israel, G‑d is our L-rd, G‑d is One." (Deuteronomy 6:4)
The Shema teaches us that G‑d is One, and that He is everywhere.
Do you know the song:
Hashem is here, Hashem is there,
Hashem is truly everywhere; (2)
Up, up, down, down,
Right, left, and all around.
Here, there, and everywhere.
That's where He can be found.
Hashem is everywhere. That's why "One" in Hebrew is Echod - Aleph, Ches, Daled.
Aleph - is 1: The One G‑d of the world, Who gives all things life, in every place, and all the time. Ches - is 8: The 7 heavens and the earth. Daled - is 4: The four far-flung corners of the world.