Propose that you subject yourself to (6)
I believe the answer is:
submit
'propose' is the definition.
(submitting is a kind of proposing)
I cannot understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for submit that I've seen before include "Hand in" , "Surrender or propose" , "Surrender, or present for decision" , "Put forward for approval or yield" , "Defer to the will of another" .)