I release all my stuff via the Creative Commons license. Basically share and share alike, giving me credit preferably.
https://creativecommons.org/licenses/by-sa/4.0/deed.en
You don't have to release yours that way. If you want to give me a creator credit, that would be wonderful. You can link to my itch account.
This last question I'm afraid I don't get. Perhaps you can clarify.
If you mean linking back to the jam, I've seen folks indicate in the credits that it was made for such and such jam, I tend to forget to do that. But will link to the jam in the game description on itch.
Hope that helps!