Windows Installer 5.0 introduced several key improvements for developers and users, which is why some modern apps require it: Install Windows Updates - Microsoft Support
Microsoft changed its distribution model starting with Windows 7. Because Windows Installer (MSI) is deeply integrated into the system's core, it is no longer released as a "redistributable" package. Windows Installer 5.0 Download For Windows 10 64-bit
There is no official .exe or .msi file from Microsoft to "install" version 5.0 on an existing Windows 10 machine. Windows Installer 5
Windows Installer 5.0 comes pre-installed on Windows 7, 8, 8.1, 10, and 11. Windows Installer 5.0 Download For Windows 10 64-bit