A) Import:

1. Click on the Import button, it will show the OpenAs window.
2. Select the OBJ file that you want to import. 
3. A new document will be opened automatically and OBJ file data will be imported into that document.  
   
   

B) About: 

    It displays the information about the product and the facility to activate your product license at any time.

Install:

The installer that ran when you downloaded this app/plug-in from Autodesk App Store, will start installing the app/plug-in.
                                                             OR
Simply double-click the downloaded installer to install the app/plugin.

Uninstall:

To uninstall this plug-in, exit the Autodesk product if you are currently running it. Simply rerun the installer and select the "Uninstall" button.
                                                                              OR 
You can uninstall it from 'Control Panel/Programs and Features' (Windows 7/8.1/10), just as you would uninstall any other application from your system.