Once the Developer tab is visible, place your cursor where you'd like to insert a checkbox, and switch to the "Developer" tab in the ribbon.

Click File in the ribbon, then select Options from the menu. In the Word Options dialog box that appears, click Customize Ribbon in the left panel. You'll see two columns showing available tabs and ...

We are using Word as an example, but the procedure is identical.: Launch Microsoft Word. Click the Developer tab on the menu bar. Click the Legacy Tools button in the Controls group section.