@luukasztim,
Tim,
Stay away from dating sites if you are young, 18 - 21 as you won't know what is real or what is not, if you are active on any. Your parents want you to marry someone of your own kind, nationality I am not sure if you get to choose at some stage in your life, I would say that you do. But not until you are no longer living at home can you make your own decisions.
From reading your other Threads, I am of the opinion that this girl doesn't even know you like her, perhaps you talk to her on-line and are infatuated with her, maybe she sees you as a friend, if she was interested in you, you would know but if you are living with your parents and they wish for you to date a certain nationality then you are stuck.
Find a job, move out and then do what you wish to do.