Do not download this font from third-party font websites. They often bundle malware or violate Apple’s copyright.
@font-face font-family: 'Apple Emoji'; src: url('AppleColorEmoji.ttf') format('truetype'); apple color emoji font download
Create a folder in your home directory at ~/.local/share/fonts . Move the Apple Color Emoji file into that folder. Do not download this font from third-party font websites