Yes i am about a month or 4 working with electron, came from C# => windows forms, winui3 and those platforms. What me makes really happy about electron is the versatility and ease of making front-end (ui), the bad thing about electron is the pages. (while apps made with electron looks like having pages, WhatsApp/ discord....) So for once and for clearity:
Build an application with Electron:
it has the app which embeds the index.html into a frame =>
in that frame make a navigation and a content goes here
inside that navigation put buttons with backend javascript in renderer.js <= because that is the backend of the WHOLE app. So there you must make the navigation logic, loading page.html files into the content div. Then make page.html backends with page.js (example) export those js lines as functions and classes and export them being modules. This works generally well, but is a bit a hasle, because 'normal webtech is omited', it is not like navigating in the browser.