You need to have an operating system to run a browser, unless you want to make a browser on bare-metal. I don't think you currently understand the topic very well.

Your project is essentially an incomplete implementation of a shell where all commands are builtins, and the interactivity is limited by what you directly programmed in JavaScript.

What you are trying to make is a lot harder than you think, you first need to emulate a CPU and go from there, not read whatever user types and try to behave like a Linux system, which ChatGPT can do already.