Submit page on Oscar in ordinary language (7)
I believe the answer is:
propose
'submit' is the definition.
(I know that submit is a more specific form of the action propose)
'page on oscar in ordinary language' is the wordplay.
'page' becomes 'p'.
'on' means one lot of letters go next to another.
'oscar' becomes 'O' (phonetic alphabet: alpha, bravo, charlie etc.).
'in' indicates putting letters inside.
'ordinary language' becomes 'prose' (I've seen this in another clue).
'p' put after 'o' is 'op'.
'op' placed into 'prose' is 'PROPOSE'.
(Other definitions for propose that I've seen before include "Put forward (motion)" , "Pop the question" , "Tender" , "Put forward a plan" , "advance" .)