docs: scenario login with email (#4741)

* docs: issue label description

* fix img naming

Co-authored-by: Maximilian Panne <mpa@zitadel.com>

docs/docs/guides/manage/console/instance-settings.mdx

@@ -173,7 +173,7 @@ To be able to use the email as username you have to disable the attribute "User
 This means that all your users will not be suffixed with the domain of your organization and you can enter the email as username.
 All usernames will then be globally unique within your instance.
 
-You can either set this attribute on your whole ZITADEL instance or just on some specific orgnizations.
+You can either set this attribute on your whole ZITADEL instance or just on some specific organizations.
 
 ## Privacy Policy and TOS
 

docs/docs/guides/solution-scenarios/configurations.mdx

@@ -46,3 +46,31 @@ This will have the following impacts:
 
 To request the organization send either the the organization id (`urn:zitadel:iam:org:id:{id}`) or organization primary domain (`urn:zitadel:iam:org:domain:primary:{domainname}`) scope on your authentication request from your application.
 More about the [scopes](../../apis/openidoauth/scopes#reserved-scopes)
+
+## Use email to login
+
+There are two different possibilities to achieve login with an email.
+
+1. Use an email address as username
+2. Use the email field of the user as additional login to the username
+
+![Domain Policy: Organization domain as suffix](/img/guides/scenarios/domain_policy_org_domain_disabled.png)
+
+### Use an email address as username
+
+To be able to use the email as username you have to disable the attribute "User Loginname must contain orgdomain" on your domain settings.
+This means that all your users will not be suffixed with the domain of your organization and you can enter the email as username.
+All usernames will then be globally unique within your instance.
+
+You can either set this attribute on your whole ZITADEL instance or just on some specific organizations.
+
+### Use the email field of the user as additional login to the username
+
+No matter how the username of your user does look like.
+You can additionally allow login with the email attribute of the user.
+
+You can find this in the "Login Behaviour and Security" Setting of your instance or organizations.
+Go to the "Advanced" section, per default login with email address should be allowed. It is possible to disable it.
+
+![Login Policy Advanced Setting: Disable email for login](/img/guides/scenarios/login_policy_advanced.png)
+