Antonio Garofalo Greetings & Welcome to Microsoft Q&A forum!
Your understanding is correct.
Azure Digital Twins doesn't currently support Cross-Origin Resource Sharing (CORS). As a result, this library cannot be used to make direct calls to the template service from a browser.
Please see the response on this thread https://learn.microsoft.com/en-us/answers/questions/747510/cors-error-when-i-query-azure-adt-using-rest-apis.
you can try using a tool like Postman to test your server's API endpoints and see if you're getting the appropriate CORS headers. This can help you isolate the issue and determine if it's a server-side or client-side problem.
Let us know if that helps or have any further queries.