Although there is no date for EOL for ADFS. Microsoft recommends migrating to Azure AD instead of upgrading to the latest version of ADFS because Azure AD provides a cloud-based identity and access management service that can help you manage your users and applications more efficiently.
You can also upgrade your farm behavior level for Active Directory Federation Services (AD FS) when using Windows Internal Database (WID)<sup>2</sup>.
If you want to migrate from federation to cloud authentication in Azure Active Directory (Azure AD), you can install Azure Active Directory Connect (Azure AD Connect) or upgrade to the latest version<sup>3</sup>.