When a new Process is added, its initial state is referred to as Active. In an Active state, users whose Role or Staff Group have permission can use the Process according to their permission level.
If you no longer want users to use or see a Process, you can Archive it. Archiving will remove the name/Process from the main Process page and will only show up under Setup.
To Activate a process, find the Process under the Top Menu >>Setup. Select the archived Process and click the Activate button in the orange box.