In order to program in Microsoft Macro Assembler (MASM), you may use Visual Studio with the through the Visual Studio Installer.
Visual Studio (VS) is Microsoft’s flagship software development product for computer programmers.
It centers on an integrated development environment (IDE) which lets programmers create standalone applications, web sites, web applications, and web services that run on any platforms supported by Microsoft’s .NET Framework.
There are three versions of Visual Studio:
Community, which is a free, fully-featured IDE for students, open-source contributors, and individuals,
Professional, which is a fully-featured IDE for small teams, and
Enterprise, which is an end-to-end solution for teams of any size.
Download the VS at the following page (Click here if the page is not displayed.):