I have to follow German and donate (4)
I believe the answer is:
give
'donate' is the definition.
(I know that donate is a more specific form of the action give)
'i have to follow german' is the wordplay.
'i have' becomes 'I've' (contraction of 'I have').
'to follow' is a charade indicator (letters next to each other) (some letters go after or follow others).
'german' becomes 'g' (abbreviation).
'ive' after 'g' is 'GIVE'.
'and' acts as a link.
(Other definitions for give that I've seen before include "6" , "Offer, elasticity" , "Donate, grant" , "Contribute - elasticity" , "Hold out" .)