Apple iPad Pro 12.9 (2018)

Tap Settings.

Tap Control Centre.

Tap the indicator next to "Access Within Apps" to turn the function on or off.

If you turn on the function, Control Centre can be used both on the home screen and while using other applications.

Tap Customise Controls.

Tap the delete icon next to the required function to remove it from Control Centre.

Tap the add icon next to the required function to add it to Control Centre.

Tap the move icon next to the required function and drag it to the required position in Control Centre.

Slide your finger upwards starting from the bottom of the screen to return to the home screen.