No brother, I do not have any windows or android system installed in my tab. But in boot option i can choose windows and it’ll go to that only up and down bubble menu. It was my friends, he tried something with a partition tool… Im not sure exactly… then it came to me and I worsened the situation.
And about the risk, since I do not have any experience with the hardware, I think I’ll wait…. and thank you verry much for your response… looking forward to here from you again when your’e free.