Hi Sian 
Have you done any of the free lessons yet to see how you manage?
The course is pretty much all through audio although there is some vocab available and some people have produced transcripts of the lessons even though the general rule is to avoid following any notes until after doing the audio work. But of course, there are always exceptions to rules!
There are people with hearing challenges who have done the course - @MarilynHames is one, as you can see from her post here: Struggling learner so I’ve tagged her here too, as she is the best to advise further.