"Though Jesus was a Son, yet learned He obedience through the things which He suffered." (Heb.5:8) Why did He have to learn? Wasn't He God? Didn't He know everything?
The main thing His Heavenly Father was trying to show Him was how to love Mankind, how to love people, how to love them enough to be willing to die for them!--To see their suffering, to have compassion on them, to want to heal their sick and save their souls, that's what Jesus learned while He was here! He learned to love us enough to be willing to choose to actually die for us, to save not only our bodies, but our immortal spirits, our souls!
Why did He have to learn those things?--Just to be forgotten and left behind when He left this World? No! To take all that with Him, all that knowledge, all that experience, and to thereby have a greater sympathy and love for us and be a greater help to us both now and hereafter! (See Heb.4:15,16.)
If even Jesus learned obedience to the Father through the things which He suffered here on Earth, how much more are we here to learn?