Microsoft offers development of Python based Web Applications and Microservices in Visual Studio. When you want to create a Web Project based on Flask, Django or some other framework, you will find templates in selection list. Your view of templates will look like below.
If you do not see these templates in your list, there is nothing to worry. It just simply means that while installing Visual Studio, you did not opt-in to installation of Python development tools. You can follow the steps below to install additional tools and services for Visual Studio.
Scroll all the way to the bottom on template list of project types. Click on Install more tools and features link.
Make sure that you have selected option for Python development
After you have selected Python development option, look towards right and select options for Web application projects.
After you have selected required options, complete the update process. Once the new tools are installed, you have will have option of using templates for Flask, Django and generic web projects using Visual Studio.