Okay reinstall Twemoji here https://launchpadlibrarian.net/360384776/fonts-twemoji-svginot_1.4-1_all.deb
It’s a Deb file and this worked for me.
As I think Ubuntu does not come with gdebi installed. Open Terminal and type or copy and paste. cd Downloads
sudo dpkg -i fonts-noto-color-emoji_0~20180424-2_all.deb
pop password in and it should install.
These are an older set, but Ubuntu should update them for you. If not then
sudo apt update
sudo apt upgrade
Then after that pop this in Terminal sudo fc-cache -f -v
You should then be able to go to this site https://emojipedia.org/people/ and pick emoji you want to use in YouTube, Twitter, in text documents, etc Bookmark the emojipedia page in Firefox.