Microsoft does not officially provide direct for Visual Studio 2019. Instead, you must create your own "offline layout," which functions as a local installation directory that you can move to other machines or burn to an ISO if needed. How to Create an Offline Installer (ISO Equivalent)
If the hashes match, the ISO is authentic and unmodified. index of visual studio 2019 iso
This is the most critical section of this article. Microsoft does not officially provide direct for Visual