This page allows you to view and manage user subscriptions.
Whenever someone purchases a membership on your site it will show up here. To create a new subscription manually, click on "new subscription" link at the top.
Depending on the payment gateway you may not be able to edit certain values. For example PayPal's subscription dates are fixed which means once user subscribes they cannot change how often they get billed (unless they unsubscribe and subscribe again).