Manage Distribution List Populations
First go over to Settings on Outlook.office.com
Click General Settings on the left-hand side > Then click distribution Groups
From here you can double click on the Distribution groups you want to make changes to. At this time we may not have group creation enabled for non-admins.
But, you can request them to be made (email it@keplrvision.com), and you should will be made the manager of the created list. Then you will have the ability to manage them moving forward.