How Do I Downloading A Discord.js Website?

I Have a website with a node.js Files,
I Want to download the node.js files To My Computer,
How I'm Doing It? When i going to error page i'm getting this:
NotFoundError: Not Found at /home/user/site/app.js:100:10 at Layer.handle [as handle_request] (/home/user/site/node_modules/express/lib/router/layer.js:95:5) at trim_prefix (/home/user/site/node_modules/express/lib/router/index.js:317:13) at /home/user/site/node_modules/express/lib/router/index.js:284:7 at Function.process_params (/home/user/site/node_modules/express/lib/router/index.js:335:12) at next (/home/user/site/node_modules/express/lib/router/index.js:275:10) at /home/user/site/node_modules/express/lib/router/index.js:635:15 at next (/home/user/site/node_modules/express/lib/router/index.js:260:14) at Function.handle (/home/user/site/node_modules/express/lib/router/index.js:174:3) at router (/home/user/site/node_modules/express/lib/router/index.js:47:12)
How Do I getting the code? (i'm need the app.js, package.json and all the files accept node_modules Folder)