I feel ya. I got a buddy who uses Bison and had no clue how to do the charges.
The key to keeping the charge from a jump-in attack is to hold back right after you leave the ground from jumping forward, doing that will give you enough time to build up the charge as you're doing standing HK or HP into Knee Press or Psycho Ball.
im learning. i can hold charges from crouching with minimal issue.
im also learning how normals are important to space and keep people off of you.
I come from the school of spamming DP and fireball, and only knowing j hk c hk
and j hk s hp dp/fireball or super.
we used to try to mimic CPU ken back in the day, when he got to 25% or less help he would spam DP.
learning Anti air vs. Vega/Sagat/Bison in SF 2 and etc used to have me from ages 8 to 13. i aint know no better.