Create Office 365 Group

There are several Office 365 group types:

1- Office 365 groups: are used for collaboration between users, both inside and outside your company. With each Office 365 group, members get a group email and shared workspace for conversations, files, and calendar events, and a Planer.

2- Distribution Lists:
used for sending notifications to a list of people. They can receive external email if enabled by the administrator.

3- Security groups:
used for granting access to Office 365 resources, such as SharePoint

4- Mail-enabled security groups:
function the same as regular security groups, except that they cannot be dynamically managed through Azure Active Directory and cannot contain devices.

5- Shared mailboxes:
sed when multiple people need access to the same mailbox, such as a company information or support email address, reception desk, or other function that might be shared by multiple people.

Let us create the first type which is Office 365 group

Go office.com or to this URL direct https://admin.microsoft.com/Adminportal/Home?source=applauncher#/groups

Then from left tree select Groups and expand it you will get option to Add New. from drop down Type it will pop up explanation of each one, let us select Office 365.

You need to enter all details, ti will check that email is valid and available and add owner.

Then press Add you will get this screen

Group now is created we will see on other post how to use it.