set up rails

app/javascript/packs/application.js

@@ -0,0 +1,13 @@
+// This file is automatically compiled by Webpack, along with any other files
+// present in this directory. You're encouraged to place your actual application logic in
+// a relevant structure within app/javascript and only use these pack files to reference
+// that code so it'll be compiled.
+
+import Rails from "@rails/ujs"
+import Turbolinks from "turbolinks"
+import * as ActiveStorage from "@rails/activestorage"
+import "channels"
+
+Rails.start()
+Turbolinks.start()
+ActiveStorage.start()