Live as you've got to, but be good! (6)
I believe the answer is:
behave
'be good' is the definition.
(I've seen this before)
'live as you've got to' is the wordplay.
I cannot really understand how this works, but
'live' could be 'be' (synonyms) and 'be' is found within the answer.
The remaining letters 'have' is a valid word which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).
'but' is the link.
Can you help me to learn more?
(Other definitions for behave that I've seen before include "Stop acting up!" , "Act properly" , "Act in a certain way" , "function" , "Comport oneself" .)