The most common and most likely answer to this crossword clue is the 3 plus 3 plus 2 plus 3 plus 5 letter word NEW KID ON THE BLOCK
I've seen this crossword clue in The Guardian
N
E
W
K
I
D
O
N
T
H
E
B
L
O
C
K
Buddy explains!
The straight part
We know that "Novice" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case novice = new kid on the block.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.