To get Gmeet URL, firstly you have to login to your gmail account. If you are not logged into gmail, click on the sign in button. Then go to https://meet.google.com/ then click on New meeting button and then select Get a meeting link to share link on selecting this link it will open a modal from here you will get Gmeet URL, just copy this Gmeet URl and paste it in Smart School Gmeet URl field.