SendGrid Integration: Connect to SendGrid with the email API
Navigate to the Email API Screen and select Web API.
Choose PHP as the language to use.
Give your API key a name. It does not matter what you enter. Once you've entered a name, click create key!
Your API key should now be visible. Copy it and past it in a text file for later. DO NOT CLOSE THE TAB.
In WordPress admin dashboard > Groundhogg > Settings > Email and scroll to the bottom.
Enter your API key and then save your changes.
Go back to SendGrid and verify that you've integrated SendGrid. Then click "Verify Integration."
In WordPress, click "Test API Connection" to send a test email via the SendGrid API.
Then click Verify Integration in SendGrid.
You should receive a message indicating you've successfully integrated SendGrid!