This article covers the process of editing the membership of Microsoft 365 distribution groups/lists.
Group members will receive any emails sent to the distribution group. Group owners are users who are permitted to edit the group's settings, including managing memberships and specified (approved) senders.
NOTE: A group owner must also be a member if they need to receive emails sent to the distribution group.
Configuring specified senders on your list allows you to restrict who may send emails to your distribution group. If specified senders are configured on a distribution group, only those senders are permitted to send or reply to the distribution group.