Add a user to an email distribution list in Office 365:
1. Sign in to your Office 365 account using your administrator credentials.
2. Go to the Microsoft 365 admin center by navigating to admin.microsoft.com.
3. In the admin center, click on "Groups" from the left-hand sidebar.
4. Select "Active groups" from the menu.
5. Locate and select the distribution list you want to add a user to.
6. In the group's details page, click on "Members" from the navigation menu on the left.
7. Click on the "Add members" button.
8. In the "Add members" dialog box, you have several options to add users:
To add users from your organization, type their names or email addresses in the search box and select them from the suggested results.
To add users from outside your organization, click on "Browse" and select "Guest users" or "External users" Enter their email addresses and click on the "Add button."
9. After selecting the users you want to add, click on the "Add" button to add them to the distribution list.
10. The selected users will be added to the distribution list, and you will see them listed in the group's members.
Once the users are added to the distribution list, they will receive emails sent to that distribution list address. It's important to note that the specific steps might vary slightly depending on the version of Office 365 or the admin center interface you are using, but the general process should be similar.
