Wont turn on

[wannabegamecreator]

Okay so I am planning on making my on gaming computer in a few weeks after I move so i got a prebuilt from bestbuy i bought a while back i was trying to practice putting it together so i took everything out and put everything in but now it wont turn on

i wish i could give specific specs but cant cause wont turn on and i don't remember them off the top of my head

i know power is going through it cause I keep on getting shocked


ty for the help in advanced

 

[wannabegamecreator]

okay i see what i did i had this plug i didnt know what is was supposed to go into so i put it into the port right next to the 4-prog plug(not exactly sure what it does) but i unplugged because i was like i put everything exactly where it should be but this 1 plug so i unplugged it put the power cord into the the fans going and then the best sound i heard the BEEEP so all good now