Quick Access Toolbar are group of command you can quickly to use. Quick Access Toolbar are top of ribbon tabs. You can add favourite command for quickly access.

By default Quick Access Toolbar are to of ribbon tabs. You can move it to below ribbon tabs by right click and select Show Quick Access Toolbar below the Ribbon

You can add command to Quick Access Toolbar by Select command from Customize Quick Access Toolbar as below picture

Or select More Command… for select all commands from Excel options

On Combo box “Choose commands from” select All Commands then find commands and click Add >> button and Click OK

Add Command from Ribbon tabs

Right click on command that you want to add then select Add to Quick Access Toolbar as below picture.

Remove Command from Quick Access Toolbar

Right click on command that you want to remove then select Remove from Quick Access Toolbar