Go to Menu -> Settings ->configurations -> E-mail Server Settings
You can check the image as shown below:
4.Select Full Access, Restricted Access, or Billing Access.
5.If you're selecting Restricted Access, or Billing Access, select the specific permissions to give each category. For more information, see API key permissions.
6.Click Create & View.
7.Copy your API key somewhere safe. For security reasons, do not put it directly in your code, or commit it somewhere public like GitHub
Host Name: " smtp.sendgrid.net " is you host name
Port Number: 587 is your default port
User name: api key is your user name
Password: Api keys which is generated will be applied in "Password"