Moving While Riding Entity Keybind

I'm trying to make a rideable mob and I had to disable riding so that I could add feeding it as well. I figured out how to make the player ride it but I can't control it since I have rideable mob disabled. If I reenable it then feeding it won't work. I have movement control and strafe control enabled but then don't do anything because it's not a rideable mob. How do I add a key bind to simply move forward while riding it and jump while riding it?