Is the jam about the game having a single choice page that you only experience once (e.g. page1 goes to page2, and page2 has the choice A/B/C, and then each of those goes to different page and then there's no more decision making.

Or, is it possible to have page1 goes to page 2, and page 2 has the choice A/B/C, where each option can display a different page that eventually links back to page2. In this case, it's the same single choice, but it's repeated. Is this allowed?

As long as only one page has more than one option to click, you can have as many branching as you want.

You can let the player restart the game (but should be a bit clear the game is restarting).