If you submit to something, you unwillingly allow something to be done to you, or you do what someone wants, for example because you are not powerful enough to resist.
e.g. In desperation, Mrs. Jones submitted to an operation on her right knee to relieve the pain...
e.g. If I submitted to their demands, they would not press the allegations.
If you submit a proposal, report, or request to someone, you formally send it to them so that they can consider it or decide about it.
e.g. They submitted their reports to the Chancellor yesterday...
e.g. Head teachers yesterday submitted a claim for a 9 per cent pay rise.