If you’re using an Apple Bluetooth keyboard, you can use keys like the Volume Up and Volume Down buttons to control the iPad volume.
You can also use the Play/Pause button and Skip buttons to control music playback. These even work while using other apps and not just the Music app. The keyboard’s brightness controls can also be used to adjust the brightness of the iPad screen.
In addition, you can use keyboard shortcuts for copy and paste. These are cmd + C for copy, and cmd + V for paste.