You need to get the ROM files on your own. Make sure you don't download a virus.
All games are not by me, they are just hosted through this website to play at school. If there is a link to support the dev and you can, you should do so.
The link to the original game if you want to support the dev: https://demo.emulatorjs.org but don't visit on school computers because it may get blocked when people visit it