Hi @Kiril
You can enable authentication for your web app running on Azure App Service and limit access to users in your organization.
App Service provides built-in authentication and authorization support, so you can sign in users and access data by writing minimal or no code in your web app. Using the App Service authentication/authorization module isn't required, but helps simplify authentication and authorization for your app.
More details refer
Add authentication to your web app running on Azure App Service
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