This repo contains the sample code for the Interchange episode More with LWC Quick Actions.
You'll need to connect to your DevHub, running sfdx auth:web:login.
If you're not familiar with SFDX and how to setup it, I recommend doing this Trailhead module.
In addition to the SFDX CLI you may need Texeï's SFDX Plugin, install it running sfdx plugins:install texei-sfdx-plugin.
Then just run the setupScratchOrg.sh script in this repo, or manually run the actions it contains.
Have fun!