Set the Restrictions for the Process Template to restrict access to view and edit processes.
To add Restrictions, go to the Templates and click three dots of the selected process.
By default, anyone can edit and view all templates.
Select individual users or groups to see and edit the template.
Once limited resection is selected - other people don't see those Templates and Processes.
Be careful. All people you give permissions can edit templates, add other people and delete existing users.
When a process is started, only users that have access can view it on the Process tab.
If the user doesn't have permission to the process, he can see the created issue, but can't view the form in the issue.
If the Template doesn’t have any restrictions, and the Processes has started based on it, so they will always be available to anyone who had access before the restrictions have been added.
Once Template has received a restriction, all subsequent Processes will be available only to those who have access.