“Comic strip style” anatomy is just anatomy. You have to learn human anatomy by drawing from life and there is no way around it. First learn to draw correctly - accurately - in three dimensions. Learn to capture the rhythm, weight and action of a pose. Then once you’ve done that to exhaustion, you can simplify it down to just a few lines. Then you can apply anatomy skills to cartoons. There are no shortcuts because simplifying is even more challenging than capturing all the details.