Top Menu >> Setup >> Select process >> Remove
We do not recommend removing a process unless absolutely necessary.
Removing a process in some cases need additional actions if there is process flow setup between the process you are about to remove and another process. Or when there are reference fields to different processes in the process.
The warnings below shows that the process you are about to remove is flowing data into the Order process and has a reference.
Other warnings could be that you have custom layout, column in different process view, or widget that is used by the process you are wanting to remove.