To create a Microsoft 365 Group, login to Outlook on the Web at outlook.office.com. On the left side navigation at the bottom, click Manage Groups. You can go directly to groups management at https://outlook.office.com/people/group.
Drop down the Create menu and select New Group.
Give the group a name and description. Then set the settings for the group or take the defaults.
Add members or choose Not now. You can add or remove members later.
The group is created. Each member that is added to the group will get a notice informing them they have been added to the group.