Provide cover for foolish type heading off for smoke (6)
I believe the answer is:
assure
'provide' is the definition.
The definition and answer can be both to do with communicating as well as being verbs in their base form.
Perhaps you can see an association between them that I can't see?
I don't understand the rest of the clue.
Can you help me to learn more?
(Other definitions for assure that I've seen before include "Tell positively" , "Cover with a policy" , "Impart confidence" , "Convince, guarantee" , "Cover by life insurance" .)