Signal to go eco: not difficult! (5,5)
I believe the answer is:
green light
'signal' is the definition.
(green light is a kind of signal)
'go eco not difficult' is the wordplay.
I cannot really understand how this works, but
'eco' could be 'green' (as in eco-friendly) and 'green' is found within the answer.
The remaining letters 'light' 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).
'to' is the link.
Can you help me to learn more?
(Other definitions for green light that I've seen before include "Seal of approval" , "Signal to proceed" , "What one has to go on" , "Given permission to proceed" , "something to go on" .)