An introduction to making a repair (6)
I believe the answer is:
prefix
'an introduction' is the definition.
(thesaurus)
'making a repair' is the wordplay.
'making' becomes 'pre' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'a repair' becomes 'fix' ('fix' can be a synonym of 'repair').
'pre'+'fix'='PREFIX'
'to' is the link.
Can you help me to learn more?
(Other definitions for prefix that I've seen before include "Meaningful construct attached to the beginning of a word" , "put at the front" , "Beginning part of a word" , "Letters added to the beginning of a word" , "add a bit on" .)