Updating FontAwesome Version

Hi there. I am a web developer who has inherited a WordPress theme built with Sage, and I am personally not familiar with how this software functions or its benefits. I am simply trying to use some icons that are included in the newest version of Font Awesome, however my project relies on an older version. Could anyone tell me how to go about upgrading Font Awesome in a Sage theme?

I attempted to follow the steps at the link below, but I got the error “ERROR: [Errno 2] No such file or directory: ‘add’”

This sounds like a permissions issue with Yarn, maybe updates to yarn or reinstalling. They recommend installing with NPM, but the first results for that error suggest you may be running this on Ubuntu so you’d want to reinstall with apt-get

As I’ve looked into it further it does look like npm was used, so I am trying to figure out how to upgrade with that. Looks like I may need to make changes in the package.json file. Am I going to need to reinstall font awesome, or will there be a way to simply download the upgrade?

Please share your package.json file.