From the bible I learned many names of god, such as EL, EL ELYON, YHVH. Does it imply us that god has many sons? From some sacred named such as Michael, Gabriel, I guess that the name of god is EL, but how about others? Is my guess correct that they are sons of god?
The name of God, as we would think it today is YHWH (or YHVH, or Yahweh, or Jehovah, depending on how you want to translate the ancient Hebrew). The other names you are seeing are called 'names of God' in the Bible, but today we would think of them more as titles. Elohim is a particularly old one and frequently used in the Old Testament; some others are:
- El HaNe'eman - The Faithful God
- El HaKadosh - The Holy God
- El Yisrael - The God Of Israel
These are not sons of God, but different things that God is called.
Michael and Gabriel are archangels, and not names of God.
Here is a helpful page on the names of God.