I will admit there is still a lot we don’t know about Energybending, but we know some stuff.
Key quote is
“In The Era before the Avatar we bent not the elements but the energy within”
Which makes sense now that we have seen Beginnings, the Lion Turtles used energybending to lend bending to the people. Energybending seems to be the natural skill of the Lion Turtles like the elements are to Dragons, Sky Bison and Badgermoles.
Aang is given energybending via energybending from the Lion Turtle and has the ability to take bending from others and based on Book 1 Air also to unlock bending within others after it was sealed.
While elemental bending focused on using Chi to manipulate your element, it seems like Energybending literally focused on manipulating Chi alone of your own and others. It clearly comes before elemental bending.
What we don’t know if Aang or Korra can actually give a non bender bending like the Lion Turtles or if Aang was only given a certain power of Energybending.
Hope this helped, but we don’t know that much about energybending.