Q:

Can't find unparented tasks in backlog on azure board

How can I see all items in azure boards which are actually not done in their right hierarchy. And further more, how can I see unparented tasks in the backlog to plan it for a sprint.
I use epics -> work for months, features -> work for weeks, user stories -> work for days and tasks -> work for hours. So I have unparented tasks and also tasks directly under features for example.

A:

Azure DevOps relies on strict tree of work items. So you must follow this hierarchy:
   Epic
    + - Feature
         + - User Story
              + - Task

Tasks are either unparented or must be linked to a User Story for the tools to work. The idea is that your Work for Weeks needs to be broken down in one or more Work for days. 
The alternative is to create a custom Epic and Feature work item in the "User Stories" level of the process configuration. That way they all end up on the "User Stories" level and can all have tasks directly under them. As a by-product you then can't easily build a tree like the one above.
It's only the User Stories that show on the backlog. Tasks only show up an Iteration backlog. If you want to do pure Kanban with different work item types on a single board including tasks, you'll have to define these all at the User Story / Product Backlog level.

A:

I think you should use iterations for weeks and use iteration backlogs to see the work scope for a week (About area and iteration paths (aka sprints), Define iteration paths (aka sprints) and configure team iterations). In this case all task (with parent features or epics and without parent) will be available on sprint backlog:
Plan task for epics:
 
Tasks in epic, feature and user story hierarchy:

Taskboard for a sprint:

If your tasks without parent and without sprint you can find it through the query (Create and save managed queries with the query editor):

