It would depend on what your English level is, especially where reading and writing emails. I am a private, US native, English speaking teacher of 12 years. I am flexible in the types of tutorials I offer, and I have often done entire courses via email. We generally begin with a level test and goal setting. Depending on your interests, I can send you assignments, send you links for practice, and then you send the completed assignment back to me. I provide feedback and further instruction and more practice.
If you can give me more of an idea of what you want, I am sure I can create a good course outline for you.
Diana Smith, M.S., Ed