This is a feature of OSEmbed Pro.

Get an embed URL of a Google Form

• Visit drive.google.com and find a Google Form you want to embed:

• In the top right corner, click the "Send" button:

• Click the little icon resembling a link:

• Click the "Copy" button to copy the embed URL of the selected Google Form:

Add the Google Form embed URL to a Joomla article

• Go to your Joomla site and log in.
• Add the Google form embed URL to a Joomla article:

The Google form embed will work perfectly on the front of your site.