Scripture gives us little information about angels, but the books that used to be considered scripture but that scholars hare decided are not scripture tell about them. I think we need to learn from these books, except everything they say must be in accordance with accepted scripture.
A study of angels that has done this checking says there are three separate classes of angels, God created six cherubim, but two fell away and Satan is one who fell away. Michael, Gabriel, Raphael, and Uriel are left.
The next order of angels are the seraphim. These are the messengers, and they fly back and forth between earth and heaven. In Revelations they are called heavenly fire. Jacob saw them as on a ladder set on the earth.
Next is the teraphim, or watchers. These are the most numerous and they have the ability to take on human form, as we are told in Hebrews 13:2. "Do not neglect to show hospitality to strangers, for by this some have entertained angels without knowing it."
These angels watch over us.