your authenication provider needs to support openid connect to use the authentication blade. they should give you the required settings.
when you use the application blade, it adds the "Easy Auth" middleware to the application. this requires no authentication code in your application. This middleware only authenticates. you can configure the token store to include the authentication token in a request header to your app so you can do authorization.
otherwise, you just add code in you application to support the provider. if it works locally, then it should work when deployed. you don't need the authentication blade in this case. (be sure to update the reply urls on the external provider).