Go on to take legal action? (7)
I believe the answer is:
proceed
This clue could be a double definition.
'go on' is the first definition.
(synonyms)
'take legal action?' is the second definition.
'proceed' can be an answer for 'take' (thesaurus). I am unsure of the 'legal action?' bit.
'to' is the link.
Can you help me to learn more?
(Other definitions for proceed that I've seen before include "Continue, go ahead" , "Move forward" , "'Continue, move ahead (7)'" , "Continue; advance" , "Follow a certain course" .)