"Unblocked" emulators typically rely on web-based technology (HTML5 or WebAssembly) rather than downloadable executable files (.exe). Because they run inside a standard web browser, they are often accessible on restricted networks unless the specific website itself has been blacklisted.
You're looking for a GBA (Game Boy Advance) emulator that can be accessed without any restrictions. Here are some popular options: gba emulator unblocked
When choosing a GBA emulator, consider the following features: gba emulator unblocked
Some even let you or a local file picker, so you don’t have to trust shady download sites. gba emulator unblocked