If you are the Microsoft Outlook Mail Client (not Webmail) on your laptop and do not see the Teams button when scheduling a meeting, you you will need to do the following:

1. Download and run this installer to remove your MS Office license - https://support.office.com/en-us/article/how-to-remove-office-license-files-on-a-mac-b032c0f6-a431-4dad-83a9-6b727c03b193
2. Then open one of your office apps and sign in with your O365 account (aka email account)
3. A new managed license will be assigned. After a few minutes Outlook will restart and then it added the Teams plugin

 
When you schedule a meeting you will see a Teams Meeting button as shown above.