The Term Store for SharePoint Online is globally used terms in organization. You can use the Term Store Management tool to create terms in a term set, or manage a term such as copy it or move it, reuse it. The purpose of Term Store is to maintain consistent data throughout our SharePoint online sites

The Office 365 admin center can be used to set up your organization in the cloud, add users, manage domains, licenses, Manage Resources, Manage Billing, Support to the end users, health check up for our sites and admincenter control.