Confluence does have a task functionality, but it doesn't have a card/board view, it's more for reminding people to do something about pages (like edit this page, or take action after the meeting documented on this page)
I think you might be looking for Jira (an issue tracker designed for tracking issues through a process, which does have boards and card representations of issues) or Trello (which is more of a pin-board and only represents items as cards on a board)
