God revealed His personal name to Moses.
When GOD spoke with Moses at the burning bush, Moses asked GOD an important question:
13 So Moses said to God, “Indeed, when I go to the children of Israel and say to them, ‘The God of your fathers sent me to you,’ and they ask me, ‘What is His name?’ what shall I tell them?”
(Exodus 3:13 OSB)
In this moment, GOD answered Moses indirectly:
14 Then God said to Moses, “I AM the Existing One.” He also said, “Thus you shall say to the children of Israel: ‘The Existing One sent me to you.’” 15 Moreover God said to Moses again, “Thus you shall say to the children of Israel: ‘The Lord God of your fathers—the God of Abraham, the God of Isaac, and the God of Jacob—sent me to you.’ This is My name forever, and My memorial to all generations.
(Exodus 3:14-15 OSB)
However, shortly after this, GOD did reveal His name.
Moses met with the elders of Israel and shared GOD's planned deliverance. They bowed to the ground in worship.
Moses and Aaron then went to Pharaoh and delivered GOD's message to let Israel go into the wilderness three days to hold a feast to Him. Pharaoh declined, instead, increasing the hardship on the Israelites by making them gather their own straw to make the bricks.
Israel then grew angry at Moses and Aaron for making their lives worse off than before. GOD responded:
1 Then the Lord said to Moses, “Now you shall see what I will do to Pharaoh; for with a strong hand he will let them go, and with a strong hand he will drive them from his land.”
2 God also spoke to Moses and said to him, “I am the Lord. 3 I appeared to Abraham, Isaac, and Jacob as their God, but I did not reveal to them My name, Lord. 4 I also established My covenant with them to give them the land of the Canaanites, the land of their sojourn, in which they were strangers. 5 I have also heard the groaning of the children of Israel, whom the Egyptians keep in bondage, and I remembered My covenant. 6 Therefore say to the children of Israel: ‘I am the Lord; I will bring you out from under the Egyptian tyranny; I will rescue you from their bondage and redeem you with an outstretched arm and great judgments. 7 I will take you as My people and be your God. Then you shall know I am the Lord your God who brought you out from under the Egyptian tyranny. 8 I will also bring you into the land I swore to give Abraham, Isaac, and Jacob, and I will give it to you as a heritage: I am the Lord.’” 9 So Moses spoke thus to the children of Israel; but they paid no heed to Moses because of their faintheartedness and cruel bondage.
(Exodus 6:1-9 OSB)
In Exodus 6:2-3, GOD revealed His personal name to Moses and Israel. In the Hebrew, the word translated "Lord" in Exodus 6:2-3 is יְהוָֹה which is transliterated "Yhwh" or "Yhvh."
Because ancient Hebrew has no vowels, translators have historically inserted vowels between the consonants. This is how we get the name "Yahweh" or "Jehovah." (In ancient English, Y and J and W and V were often in place of each other.)
It is often inferred that, because GOD told Moses "I Am" sent him, that this means that GOD's personal name, YHWH, means "I Am." This makes sense because, according to NAS Exhaustive Concordance, the root word is "havah," meaning, "to become."