Your teacher may have created school logins for your class, if not you can register yourself or just play as a guest.
Once you have logged in or chosen to play as a guest you can have a look at all the games and make your choice.
This will return you to your dashboard where you can select your level by clicking on ‘Show Levels’ then choose from level 1 to 10.
Next choose your skill, choose ‘select none’ to deselect all skills if you wish to choose just a few skills.
Selecting Play will now allow you to play your game with your chosen skills and level.
Note that if you log in you can track your progress.
If you feel a little insecure on topics like directed numbers (many students do) you may find this a great way to practise.