Can I change the path of the default home page?

Because I customized a plug-in for sso, it contains its own login interface, and any user who needs to log in must use this as the homepage. Is there any way or parameters that can be changed?

You could edit the core code or if using a plugin one way is to use a custom view engine and direct the homepage to your custom page
I assume you still need to get to the original home page so you could have some code to check if you are logged in and if so goto the old homepage instead of the custom page