How do I get a Word document window to add a button

Step 1th, open the Word document window, click the Office Button → Word Options command, as shown in Figure 1

Step 2nd, in the Word Options dialog box, switch to the Custom tab, and then click the command you want to add in the Select commands from list, and click the Add button, as shown in Figure 2

3rd, repeat step 2 to add multiple commands to the Word Quick Access Toolbar, click reset → reset the Quick Access Toolbar only button to restore the Quick Access Toolbar to its original state, as shown in Figure 3