The saker.msvc package runs as part of the saker.build system. The packages are distributed using the saker.nest repository. In order to install them, see the installation guides for saker.build and saker.nest.
You also need to have an appropriate installation of the MSVC toolchain available on your machine (or at least one of the build clusters).
Having the Windows SDK installed is also strongly recommended.
You can use the saker.msvc package by referencing the contained tasks in it.