HAVING PROBLEM INSTALLING KALI LINUX ON MY LAPTOP WHICH AS NOW AFFECTED MY WINDOWS 7 OS

Hello!

I Am New to This Website and I Have Spent Sometime Looking Over Past Threads to See if Some Would Help Me with My Problem. But My Biggest Obstacle Is That I Am Just a Layperson with Very Little Knowledge of Computer Lingo. So I Am Hoping That Someone Could Help Me Here and Go Through the Steps with Me in Plain Non-Technical Language.

I tried installing kali linux on my windows 7 ultimate O.S, because i learnt that's the O.S hackers work with on here. After i downloaded kali linux 64bit torrent from kali.org/downloads following the installation guide from this site (Same way as installing backtrack 5 which is now outdated), After downloading the Kali Linux 64 bit Torrent which was about 2.84gig I was able to burn it into a flash drive in which i booted(''not sure if i actually did booted it but i did run the setup.exe is that what booted means'') from for the installation because i had no DVD-CD to make use of instead. After i ruined the setup.exe from the flash drive where i burn the kali linux into using rufus, It got to a point where i was ask to reboot my computer. After rebooting my computer, i saw another O.S which was named kali linux so so so I can't really remember, I clicked on it and kali linux showed up and i was asked to continue with the installation, I choose my country and click cotniue it was detecting if there was a DVD-CD in my CD ROM but finally it detected the flash drive in which i burned the actual download file into so the installation continued and then I got to a point where i was asked disk partitioning i guess i was so dumb here because i choose use entire disk. I was a bit overwelhmed thinking the kali has been installed on my laptop then i was taken to a time zone page i choose Estern and then i got to a mirror page i choose yes then it asked me to choose a mirror i choose several mirrors but it keeps saying the same thing like internet problem or this kali is not support, I turn off my laptop by pressing the off/on botton and after turning my laptop back on, everything became blank i didn't see my windows 7 O.S nor the kali linux O.S now my laptop is just useless because i can not do anything with in, i al using a friend laptop to write this. Please I am seeking help from everybody who knows what i can do to recover my windows 7 O.S and the files in it and also how i can successful install kali linux on my laptop without my windows 7 getting affected again.

Thanks in advance

Samuel