Pre-requisites:
Required role privilege 'Manage Workflow Rules' on the project where a workflow instance is to be canceled.
Follow the steps for checking progress on a workflow instance then go to the particular workflow instance on which you need to cancel workflow.
Do a right click on the node where workflow is currently moving and select 'Cancel Workflow' option to cancel this workflow instance. The right click option to cancel workflow won't appear for any actions not yet executed as part of the selected workflow instance.
Note: Canceling a workflow won't automatically clear tasks that would have already been assigned as part of the workflow and are pending to complete. Such tasks need to be cleared manually using 'Clear Tasks' option for files / 'Clear Tasks' option for forms as applicable.
By performing above steps, only the selected workflow will cancel for selected object i.e. file or form or custom object. If there are other workflows applied on same object, they will remain unaffected.
In case the workflow on selected file / form / custom object is in 'Failed' status, it cannot be canceled directly. It has to be first resumed and only then the workflow on selected object can be canceled. Click here to learn how to resume a failed workflow.
Check: FAQs
Related Articles: Transition a Workflow Instance in Progress
Next Collection: Create a Workflow (in a Project Template)