To play games, you'll need to load a ROM (a copy of a game). This usually involves selecting "Open" or "Load ROM" from the emulator's menu, then navigating to where your ROM file is located.
This indicates the file format is a "big endian" Nintendo 64 ROM (sometimes referred to as the .z64 extension), which is the standard format required by most N64 emulators and ROM-hacking tools. baseromusz64+download+link
The extension .z64 indicates the ROM is in format, which is the standard requirement for most build tools. To play games, you'll need to load a ROM (a copy of a game)
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