Hello Debo,
If you are wanting to assign tests for your daughter (such as the 2015 mock tests), you will need use the free credits that were given to you with the mock test booking and you can add to those by purchasing some more if they run out (see your dashboard for this information). You can assign tests to your daughter when you logged in to your parent account.
Please watch this video about how to assign tests in COAsT.
I hope that helps. It is a good idea for students to try some of the 2015 Mock Tests before they take one at a test centre.