Manage All My Leads is a function you as an admin make available to your agents to allow them to adjust availability within Lead Assign and view the list of leads they’ve been offered. Don’t worry they can only see lead information about leads they’ve accepted.
When your agent receives a lead and goes through the process to accept/decline it, if they click/press on the little “X” in the top left corner of the page they’ll be brought to a login page. Once there they just login with their email used within the system and they will have a severely reduced admin view. They will only see the leads tab and an availability toggle. The toggle defaults to being off so if you want to allow your agents to handle their own availability just enable the setting found at the top of advanced settings.
If an agent sets themselves as unavailable they will not be able to receive leads but they can still interact with the leads they have. This allows agents on vacation or who already have more than a full plate to opt out of receiving leads until the Admin or they themselves re-enable their availability.