New user - Task as child of and assignable to cards in Decks?

I find it strange that there is no way to add a Task to a card and that you cannot move them from card to card. It appears to only be stand alone for tasks

A card is sort of a Sub goal to build upon to a larger thing, and that card may have a series of tasks that may require assigning to or waiting for others for example.

Am i missing something?