trouble with wifi and installin windows 8.1

I have win 7 ultimate(pirated) and I have installed and uninstalled windows on my pc many times but this time when I wanna dual boot my pc with windows 7 ult and windows 8.1 pro and I have also created a bootable win 8.1 usb. I have also made a separate(partitioned) drive for win 8.1. I was just one step away from getting win 8.1 but when I selected the disk I get a message saying unable to find or create partition something like that. I also tried instaling win 7 again the same prob came also I am not able to find my wifi connection in my pc even though I ve connect it with the cable and also able to connect to wifi on other devices.
I tried a lot to solve these problems but could not succeed, afterall I'm just 14. Please help me out guys!!