Your task status is the square that appears to the left of all your tasks in your To Do List.  If you click on this square a new menu will pop up where you can choose to mark your Task as "Finished," "In Progress," or "Delayed." See below:

Your priority labels appear as small flags to the left of your Tasks. You can click on these flags to give your task a priority of high (red flag), medium (yellow flag), low (green flag), or none (white flag). See below:

If you don't like the colors of your priority flags or status icons, or even if you want to rename what these labels are you can do so in the "Customize" screen of your To Do List labels. Follow the steps in the image below to learn how to change these labels:

With these customization options, these labels and status can be changed to perfectly suite your needs and it can be individualized for each To Do List in your account.