For your first question. You must learn switches and variables. You'll need to do something like set a switch at the end of the event and then create a second blank page in the event that only activates if that switch is on. This new page doesn't have any information in it so the autostart event ends right then and there. If you don't understand the concept, there's plenty of tutorials out there.

For your second question, all you need to do is make sure the map you're linking to is created, go into the event layer, right-click the tile you want to link to, and select the move event option. The rest is self-explanatory.