Adding a third-party repository (like this one) is easy. Just add the following lines to the end of /etc/pacman.conf :
[arch-repo]
SigLevel = Optional DatabaseOptional
Server = https://raw.githubusercontent.com/VijayakumarRavi/$repo/main/$arch
Then, sync the repositories and update your system with:
sudo pacman -Syyu
And, then:
sudo pacman -S name-of-package