Firstly, please understand that this forum is run by volunteers, we simply can't process things ASAP.
The menu starts out initialised and running, so once you build it onto a board it will immediately start if everything is configured correctly.
You take over the display when you want to use it yourself. You'll be called back in what's often referred to as a "game loop" where you refresh the screen if you need to. It will give you the current value of the encoder and also if the button has been pressed. This suffices for some but not all. When you need more control over the input, you can manually provide the input facilities yourself.
Take over display:
http://thecoderscorner.com/products/arduino-libraries/tc-menu/renderer-take-over-display/
Providing input to tcMenu manually:
http://thecoderscorner.com/products/arduino-libraries/tc-menu/menumanager-and-iteration/#controlling-the-menu-items-manually