Here is an example of a multi-region WebApp - https://learn.microsoft.com/azure/architecture/example-scenario/sql-failover/app-service-private-sql-multi-region?WT.mc_id=AZ-MVP-5004796
The Visio file can be downloaded and modified to your liking. Give the Azure Architecture Center a browse. https://learn.microsoft.com/azure/architecture/browse/?WT.mc_id=AZ-MVP-5004796
Here is a guide on deploying an ASP.NET application to Azure App Service with SQL: https://learn.microsoft.com/azure/app-service/app-service-web-tutorial-dotnet-sqldatabase?WT.mc_id=AZ-MVP-5004796