manage_inventory.routing.yml

# Route name can be used in several place (links, redirects, local actions etc.)
entity.content_entity_manage_inventory.canonical:
  path: '/content_entity_manage_inventory/{content_entity_manage_inventory}'
  defaults:
  # Calls the view controller, defined in the annotation of the contact entity
    _entity_view: 'content_entity_manage_inventory'
    _title: 'Event Content'
  requirements:
  # Calls the access controller of the entity, $operation 'view'
    _entity_access: 'content_entity_manage_inventory.view'

entity.content_entity_manage_inventory.collection:
  path: '/content_entity_manage_inventory/list'
  defaults:
  # Calls the list controller, defined in the annotation of the contact entity.
    _entity_list: 'content_entity_manage_inventory'
    _title: 'Event List'
  requirements:
  # Checks for permission directly.
    _permission: 'view event entity'

entity.manage_inventory.add_form:
  path: '/content_entity_manage_inventory/add'
  defaults:
  # Calls the form.add controller, defined in the contact entity.
    _entity_form: content_entity_manage_inventory.add
    _title: 'Add Event'
  requirements:
    _entity_create_access: 'content_entity_manage_inventory'

entity.content_entity_manage_inventory.edit_form:
  path: '/content_entity_manage_inventory/{content_entity_manage_inventory}/edit'
  defaults:
  # Calls the form.edit controller, defined in the inventory entity.
    _entity_form: content_entity_manage_inventory.edit
    _title: 'Edit Event'
  requirements:
    _entity_access: 'content_entity_manage_inventory.edit'

entity.content_entity_manage_inventory.delete_form:
  path: '/inventory/{content_entity_manage_inventory}/delete'
  defaults:
    # Calls the form.delete controller, defined in the contact entity.
    _entity_form: content_entity_manage_inventory.delete
    _title: 'Delete Event'
  requirements:
    _entity_access: 'content_entity_manage_inventory.delete'

manage_inventory.inventory_settings:
  path: 'admin/structure/content_entity_manage_inventory_settings'
  defaults:
    _form: '\Drupal\manage_inventory\Form\InventorySettingsForm'
    _title: 'Event Settings'
  requirements:
    _permission: 'administer contact entity'