Microsoft provides these offline installers via their Download Center. Use these direct URLs:
The Microsoft .NET Framework 4.7 is a major update to the Windows .NET runtime and class libraries, offering performance improvements, enhanced accessibility, cryptography updates, and support for newer Windows versions. The "dotnetfx 4.7 full x86-x64" package is the offline/full installer that supports both 32-bit and 64-bit systems. dotnetfx 47 full-x86-x64.exe