If you want to send a new SendGrid email every time you receive a Gravity Form submission, you can do that using Zapier.
You will need:
To connect your Gravity Forms account to Zapier, you will need the Gravity Forms plugin with the Zapier add-on installed. You will also need a form created in Gravity forms. To get started with Gravity forms, and for information on creating forms and installing the add-ons that you will need, check here. Information for getting started with Gravity Forms on Zapier can be found here.
To link your Gravity Forms to SendGrid, you must have an active SendGrid account. To learn more about getting started with SendGrid basics, start here. For more information about getting started with SendGrid on Zapier, go here.
Now test the Zap to make sure it works. Once you’re satisfied with the results, new Gravity Forms submissions will automatically send an SendGrid email.
If you ever want to change this Gravity Forms and SendGrid integration, just go to your Zapier dashboard and tweak anything you'd like.