Templates consists of sections and fields. A section contains one or more fields and can provide additional context to its fields. Two sections could contain the same fields, but have different meaning. For example: 'Billing address' and 'Visiting address'.
Fields are used to store information in. The configuration of a field dictates how a field can be used and what kind of information it holds.
To edit the template:
Log in as an administrator.
Navigate to Settings and choose Add-ons or Apps.
Find Atlas CRM in the menu on the left.
Open the Company template or Contact template.