Alternatively, you can set your localhost to 0.0.0.0 but this is usually better for servers where you also likely need to set up reverse proxies/https, login/authentication, and open up ports and manage firewalls:
But all of those requires a strong knowledge of networking and may be a lot of work if you're new to it.
Also, in the last post I attached, be sure to see the follow up comment on using named multi-user sessions too with ngrok. This can help you track multiple users' sessions.