Since this is a P2P release rather than a Scene release (like FLT or RUNE), it often comes as a "Portable" folder. You simply extract the contents and run Bannerlord.exe from the /bin/Win64_Shipping_Client/ directory.
Version 1.0.1 is considered a stable base for many "Legacy" mods, though newer mods typically require the v1.2.x series or higher. Mount.and.Blade.II.Bannerlord.v1.0.1.4833-P2P.t...
This specific build focused on critical stability and bug fixes encountered by players at the official launch: Since this is a P2P release rather than