State, etc., wrong to join up (7)
I believe the answer is:
connect
'join up' is the definition.
'connect' can be an answer for 'join' (synonyms). I'm not sure about the 'up' bit.
'state etc wrong' is the wordplay.
'state' becomes 'conn' (I can't justify this - if you can you should give a lot more credence to this answer).
'wrong' indicates anagramming the letters.
'etc' with letters rearranged gives 'ect'.
'conn'+'ect'='CONNECT'
'to' is the link.
Can you help me to learn more?
(Other definitions for connect that I've seen before include "Bring together" , "Link together" , "Join - link" .)