Step 1 – To use Sidecar on your Mac and iPad, first of all, open System Preferences on your Mac then click on the Sidecar preference pane. If it isn’t there, your Mac’s too old to use Sidecar.
Step 2 – You can set where the Sidecar Sidebar and Touch Bar appears on your screen, if at all. When you’re done, look in the pull-down menu labelled ‘Connect to’, and choose your iPad.
Step 3 – There’s a brief flash, and your Apple devices connect, sharing screen space between your Mac and your iPad. Your iPad can now be used as an input device or second screen when used alongside your macOS device.
Step 4 – To move your iPad to the other side of your Mac, open System Preferences > Displays > Arrangement. Drag the smaller blue shape around the larger one, until it’s where you want the iPad to register.
Using the iPad as an Input Device
With Sidecar, you can also use your iPad as a graphics tablet. According to Apple, any Mac app that supports stylus input works in this way, but the company has also come up with a preliminary list of apps that you can use with the Mac, iPad, and Apple Pencil:
Final Cut Pro
To use Sidecar, your Mac must be one of the following;
iMac 27-inch 2015 or later
Mac mini 2018 or later
Mac Pro 2019 or later
MacBook Pro 2016 or later
MacBook Air 2018 or later
MacBook 2016 or later