Let’s me help you setup properly then. First I have few questions and suggestions as well.
What OS are you using, if it’s windows OS then you can run the npm start instead of make site. But since you already installed all dependencies with the make setup-libs, what you can do here is delete your node_modules first and run npm install and npm start sequentially. If you are using other OS like Linux or Mac, you can also delete your node_modules and run make setup-libs and then make site again. Be certain you have internet connection. Tell me if this solves your problems. Please send a follow up with screenshots.
Include as much detail in the description of your issue as you can. What code changes are you making? If you have an error in your code, the page may not build and consequently not show.
If you can’t get it figured out here, be sure to join the Websites meeting on Mondays. Details here - https://meet.layer5.io
Try to reload the browser when you make these changes. Also, some changes might require you to restart the server. You can add some random background-color CSS to be sure changes are not rendered. It might be that changes are rendered but not just working as you expect it to.
From your logs it’s quite clear that env-cmd is a package that is not installed, prolly its not your fault but the package.json file is missing this required dependency.
You can have it with npm i env-cmd, Probably someone else may be facing the same issue. If you can land a PR with this Fix that would be so kind of you.