As a team owner you can invite new members to a team or remove existing members. There is no limit to the number of members a team can have.
To manage the membership of a team, click on your organisation and the go to the Users tab.
The team page lists the team's current membership:
In here you can see for how long each member has had access for.
From the same place, the owner can revoke an invitation or remove a team member, based on whether the invitation is pending or accepted.
Other members, whom have been added by the owner, can also create an organization, which will not be visible to the initial owner, creating therefore a new entity.
Meaning, if firstname.lastname@example.org were to create a new organization, it will look just like the pictures from above.
If you wish to change the name of your organisation, simply head to the Settings tab and you will find the Organisation name field.
In the same tab, you can also find the button to remove your organisation,
Upon pressing the "Remove Organisation" button you will have to confirm on the pop-up that you wish to confirm to delete your organisation.