Starting up the Magic Keyboard is pretty simple, since most of the time it doesn't require the same complicated booting process as a computer or phone.
First, make sure your Magic Keyboard has batteries installed (if it's battery-powered). The battery compartment is usually located on the back of the keyboard, and you can open it and insert the appropriate number of batteries, paying attention to the corresponding positive and negative poles.
Once the batteries are installed, just hold the Magic Keyboard close to your Apple device and make sure the device's Bluetooth function is turned on. Then, press any key on the keyboard and it should automatically pair with your device.
If this is your first time using the Magic Keyboard, or you've replaced your device, it may require you to enter a pairing code. But usually, the Magic Keyboard has a preset pairing code, such as "0000", or it will automatically pair without entering a pairing code.
Once paired, you can start typing with the Magic Keyboard.