My hands often shake and after a while of sitting still i start to feel anxious and have to stand up and do something i'm 19 and i don't use drugs

Check up: Go to your physician. They will check and see if there is a medical condition explaining your symptoms. If nothing comes up ask for a referral or go see a therapist. Cognitive behavioral therapy is a good treatment approach for anxiety. They will teach you how to manage the physical feelings as well as the thoughts that drive and support your anxiety.