Chord structures are built in thirds above each note of a scale. Learning proper chord structure is key to the fundamental understanding of how to improvise. Without it, you won’t get very far at all. This course describes chord structure in detail and gives you specific exercises to practice.
Learn how to comp with your left hand and play the proper scales with the right. This will help you with hand independence. You need this skill because eventually, you will be able to improvise with your right-hand while your left-hand keeps time. The left-hand comps, the right-hand solos.