Dear W.B.,
I believe that any age can be a great age for learning when we have the desire. You need a professional who can analyze your strengths and weaknesses, and then carry out a learning project designed especially for you. I suggest that you find a speech/language pathologist who can assess the skills that underlie your written language. Some examples might be the auditory discernment of speech sounds in words, and auditory and visual memory.
The speech/language pathologist can find successful ways for you to rehearse weak skills. As you improve, you will be more able to take advantage of other educational opportunities such as tutoring or community college courses.
Best Wishes,
Ruth Alice Jurey, M.S.
Speech/Language Pathologist