The bird to provide a quill (3)
I believe the answer is:
pen
I believe this clue is a double definition.
'the bird' is the first definition.
(pen is a kind of bird)
'a quill' is the second definition.
(I've seen this in another clue)
'to provide' is the link.
(Other definitions for pen that I've seen before include "International writers's organisation" , "Write" , "See 20" , "Swan for the writer" , "International Association of poets, playwrights etc" .)