Forward_Auth or Authcrunch?

My organization has purchased a web based application They want me to expose it to the Internet so as to be able to access it remotely. Among other things, I have placed a reverse proxy in front of the app to help secure it.

I am a relative newbie to caddy. In fact it has been a long time since I have had to deal with web servers, proxies, and reverse proxies. So far I am very impressed with Caddy! It was pretty straight forward to configure and setup. I even was able to configure it to block requests by IP addresses from a trusted web list and by geo location.

My main concern now is the login for the app. It is a straight forward users/password combination. It does not appear to use any type of modern authentication or MFA. Since I am using a reverse proxy I thought maybe I could redirect to Microsoft and have my users login there first before accessing the apps login screen. Is it possible to use forward_auth to forward to my Entra/Azure for authentication, or do I have to use Authcrunch. I have been looking at Authcrunch, but the documentation for a newbie like myself is not that intuitive. I have read the docs for forward_auth and I don’t think this will work. Any guidance would be greatly appreciated.

Thanks!