updated: converted to answer.
Please check this doc, Composites / CallComposite / Join Existing Call As Teams User - Join Existing Call As Teams User ⋅ Storybook (azure.github.io) - This describes how to join call as Teams user.
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https://github.com/Azure-Samples/communication-services-authentication-hero-nodejs
Also, kindly take a look at the samples below and you may need to customize based on your requirements.
Audio/Video Calling from a Custom App into a Teams Meeting: This tutorial on Microsoft Learn guides on how to use ACS in a custom React application to allow a user to make an audio/video call into a Microsoft Teams meeting
Other related samples:
UI Library Sample - File Sharing using UI Chat Composite
UI Library Sample - Creating a Call Readiness Experience
Added additional Teams’ tags to receives insights from the targetted audience/SMEs.
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