I have done today a task and they give 6 cents 3 for the task and 3 for passing the training mode
but why they don't let me to do more

Can you be more specific ? What is the task name and more details.

This is very unusual to be paid for the training pages.

Sounds like you got one of those screener tasks where you answer some questions to determine if you are qualified to receive future tasks.

What messages did you get ?

If it was a screener, you would normally be contacted at a later date or receive new tasks that follow, you have to wait (pending qualifications).

Otherwise if you can't do a task it is because there are none left to do at the moment or they determine you are not qualified to do more.