https://itch.io/jam/tasjam-for-health/topic/7595/how-to-submit-to-itchio
Those are instructions for another jam, but they should be relatively easy to follow. The big take away is the following:
- Join Jam
- Submit game
if you could tell us what engine you are using, etc maybe I can take screenshots of the process
Anyways, I hope it helps
ps: you posted this an hour ago. Sometimes things go unanswered for a couple of days, weeks, etc. Don't worry too much about it.