header and footers

Dear Marc
I think musescore is great. thankyou for inventing it!!
I need help with assigning a part name to my header. im trying to do it with the $f a. and $p stuff but I would like it to automatically create the part name (using the same window ...if this is possible...?)
. I am not tech-savvy so ill revert to just command T... for text if needs be.

Im completely self taught and think I must have done in the region of over 50 separate items on musescore.
its great.
thankyou
christine