I made e-mail but without asking my parents because I need it to ask about Islam, but my parents don't know that if that. So is it right if I continue of using e-mail or should I cancel it?
All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.
If you strongly believe that your father will not object when he knows that you have an e-mail account, then you may use it even if he does not know.
However, if you think that he will not permit you to use an e-mail or he has already hindered you from having one, then you are not permitted to use it. But, if you do not have any source to gain Islamic knowledge other than by e-mail and you are not using it for any evil purposes, then you are permitted to use e-mail even if your father does not permit you. In this case, you are not obliged to obey your father as he is hindering you from fulfilling a good and religious obligation. The Prophet said: “Obedience is only in what is permissible”. [Al-Bukhari and Muslim]
Allah Knows best.
You can search for fatwa through many choices