Welcome to m64p (mupen64plus + GLideN64 + a GUI)
You can download binary builds for Windows and Linux here. There are 32 and 64-bit builds, the Linux build is built on Ubuntu 16.04
m64p uses mupen64plus-gui, a brand new mupen64plus frontend written in Qt5. It supports all thing things you’d expect from a frontend (savestate management, pausing, screenshots, etc..).
m64p comes bundled with GLideN64 for the graphics plugin. It should give you the best out-of-the-box experience available for N64 gaming.