Possibly save 2 hours of your time: If you create your iterations on the Project, it may not show up on the left pane for Backlogs > Future iterations.
On VSTS, when you create a new Project, it will also have a default Project / Team. There are similar settings for both Project and Project/Team.
To fix this you first have to make sure your iterations are created in Project settings >> Work >> Iterations.
Then you go to Project / Team settings, and select those iterations from Team settings >> Work >> Iterations. The iterations selected below will appear in the Backlogs hub for your team. Each iteration will have a backlog and board to help your team plan and manage work.