As Memberships expire, you can advance the expiration date, set the status and apply a fee to their invoice by renewing the Membership.
From Constituents, search and open the Constituent you want to renew. Scroll down on the sidebar to find Memberships and click on the membership you wish to renew.
You can change the level and price as necessary. Keep in mind the expiration date will automatically advance when changing the level. When ready, click Renew Membership.
From there, confirm the new expiration date and click Save.
This will apply a fee to their invoice, update the expiration date, and set the status to Active.