I’ve never actually had an MS nurse in the consultation with a neurologist. So I suspect (as with everything else related to MS), it depends on your local service.
If you are discussing disease modifying drugs (DMDs) then having an idea about the options that might be offered to you is useful. If you’re unsure at all, have a look at https://www.mstrust.org.uk/about-ms/ms-treatments/ms-decisions-aid
Otherwise, have a think about what you do and don’t know, write some notes for yourself as to what you want the neurologist to know, and don’t forget to take the notes out during the appointment (I had an appointment yesterday, wrote notes beforehand and forgot to take them out so missed a few things I’d wanted to tell him!)
If you have someone to take with you, that might help as they may remember things you forget.