Is it possible to somehow control the power of the board in the Arduino Uno?

Question

Arduino

Is it possible to somehow implement the mechanics of turning the board off / on in a regular Arduino Uno? Of course, a simple option comes to mind with breaking the power circuit from the Kron battery, but this option is not suitable, due to the presence of a case for the Arduino itself. Therefore, I would like to start powering the board by pressing a button on the external case.
Initial data:
Fig 1. Case, button, Arduino
Desired design:
Fig 2. Set the switch to the "on" position, and get a working device
Good people, knowledgeable, tell the Nubas solutions.
Thanks in advance, everyone!

Answer 1

If you really need to physically break the power, then only as suggested above, with soldering. If you just need the functionality of turning the device on and off, then hang the switch on one of the pins. If open - drop the controller into hibernation (sleep or power down), if closed - wake up.
True, the arduino has a stabilizer with its own consumption of a few milliamps, so the battery will still slowly drain out.