Lively performer smashing up boat and car (7)
I believe the answer is:
acrobat
'lively performer' is the definition.
'acrobat' can be an answer for 'performer' (I have seen 'Gymnastic performer ' mean 'acrobat' so perhaps 'performer' could also mean 'acrobat'). I'm unsure of the 'lively' bit.
'smashing up boat and car' is the wordplay.
'smashing up' is an anagram indicator.
'and' is a charade indicator (letters next to each other).
'boat' put after 'car' is 'carboat'.
'carboat' anagrammed gives 'ACROBAT'.
Can you help me to learn more?
(Other definitions for acrobat that I've seen before include "Circus gymnast" , "Performing gymnast" , "performer of risky feats?" , "User of five ac" , "Gymnastic entertainer" .)