You’re not doing it wrong. Forecast behaves like perspectives of type ‘Individual Actions’, which surface all the matching actions in a flat list and (with certain sort orders) places parent actions/projects after their child actions (because if you are completing them one by one the parent action becomes available last).
It’s often been requested to be able to have a different presentation in Forecast. For example, automatically grouping branches of actions, so that you can collapse ‘checklists’ of parallel actions.
The only way to avoid seeing all individual actions in Forecast is for them to not have a due date. This means you can’t give the project a due date, and you must create a separate task which represents ‘finish the project X by due date D’. This task could be the first task in the project, or placed outside the project (and it points to it by including a link in the notes).
See also this thread:
