Call on and you'll get a chance to participate (4-2)
I believe the answer is:
look-in
This clue might be a double definition.
'call on' is the first definition.
(thesaurus)
'a chance to participate' is the second definition.
(I've seen this before)
'and you'll get' is the link.
I am not very happy about this link. Some or all of it may belong to one of the definitions.
Can you help me to learn more?
(Other definitions for look-in that I've seen before include "Watch TV (colloq.)" , "Make a short visit of visual sort?" , "Chance of success" .)