Use the DISM command with an offline source as shown in Method 3. If you lack a Windows 10 ISO, download the Media Creation Tool from Microsoft and create an ISO.
The search for is a classic example of legacy software needs colliding with modern OS design. The correct answer is not a standalone installer from a third-party website, but rather the built-in .NET Framework 3.5 feature of Windows 10. net framework 2.0 v 50727 download 64-bit windows 10
If the Framework64 folder exists and contains files, you have the 64-bit runtime. Use the DISM command with an offline source