Deleting a template is irreversible. Please make sure you want to delete the template before proceeding. Once deleted the template won't be available anymore for its use, or appear under your template list, if a flow is currently using the template it will stop working.
To delete a template, go to your templates click on the Delete button in the right side menu of the template you want to delete.
On the next screen, you will be asked to confirm the deletion. Click on the Yes, delete button to confirm.