You and I tucked in debutante's American anorak (5)
I believe the answer is:
dweeb
'american anorak' is the definition.
'dweeb' can be an answer for 'anorak' (I've seen this before). I'm not certain of the 'american' bit.
'you and i tucked in debutante's' is the wordplay.
'you and i' becomes 'we' (we means you and I).
'tucked in' is an insertion indicator (I've seen this in other clues).
'debutante' becomes 'deb' (short for debutante in fashionable society).
'we' going within 'deb' is 'DWEEB'.
Can you help me to learn more?
(Other definitions for dweeb that I've seen before include "Antisocial guy" , "Nerd - wimp" , "Insignificant student" , "Fool" , "misfit" .)