Rather than a live lesson, where you interact with your tutor inside the lesson space, a written lesson does not require back and forth interaction with your tutor. You can submit a written lesson to a tutor, indicating a duration that you'd like them to send working on an explanation to a problem, concept, assignment, or paper that you're working on. The tutor will spend the indicated duration working on the written lesson, and send the explanation back to you before the due date you select.
Please keep in mind that written lesson explanations will not solve the problems or complete the assignment/paper for you. Rather, the tutors will provide the steps and helpful explanations necessary so that you're able to complete the work on your own using their provided help.