I have a need to sync all the properties present in Active Directory to SP Online User Profiles. Can anyone provide the steps to do so?
SharePoint Online user profile syncs properties from Azure AD. There are fixed set of properties that it syncs which cannot be changed. See this link for list of properties that SharePoint online syncs from Azure AD. If you would like to sync additional properties you will have to sync manually using a custom application. There is a user profile bulk import API that you can use to import required properties in a scheduled fashion.