I have searched all over and have not been able to find anything that says what is used or how to toggle a switch track. This is a very cool mod, but is often not intuitive.

Redstone signal on the long tie, my guy. Also, the wiki is being updated with the latest changes.

Thank you, and thank you for the quick reply.
I have a 5-year old that is big into minecraft and trains and I am trying to set him up. Is there a way to make it so while in creative mode, the trains dont require fuel and water?

thank you so much

In the immersiverailroading config, there's an option called allGaugesRequireFuel.

you may also want to set allowDieselEnginesOverheat to false and explosionsEnabled to false, lest you blow up a steam loco.

perfect, thank you again