Morph targets for hands, legs, muscles

Hello, I am looking to create a character creation system
While I have a solid understanding of how this is going to work via blueprints, I can’t find any information about hands/legs having morph targets.
I only found facial morphs and I am wandering if hand/legs morph targets are possible? Is there any tutorial on adding morph targets to anything other than face? I am a beginner in animation, I know little to nothing

quick bump