Obtain the NDP452-KB2901907-x86-x64-AllOS-ENU.exe file from the official Microsoft Download Center.
Because Windows 7 is older, you may need to update your "Root Certificates" if the installer says it can't verify the file's digital signature. net framework 45 2 offline installer for windows 7 top
If the installer says a newer version is already installed, you likely have .NET 4.6, 4.7, or 4.8. You don't need to downgrade; newer versions are generally backward compatible. Obtain the NDP452-KB2901907-x86-x64-AllOS-ENU