I'd guess OP is familiar with the installers. Their problem is because those installers *do not work* on Windows 10. This is because .NET 3.5 is now a component of windows itself.
If you run that standalone installer on Windows 10, you just get this dialog:
You can either download and install it via Windows Update- or not install it at all.
The only other option is to add it via Windows Features (Turn Windows features on or off) Which also requires either Windows Update, or some form of WIndows 10 installation media matching the installed version of Windows.