My Wire is cut in half, what to do?

So the charger of my phone (the wire) was cut in half and im seeing two wires inside. One black one white. I peeled the cover of black , connected it and covered it with electrical tape and i peeled the white and do the same thing. Now they are like separated again and then i covered both with electrical tape so it won't look bad. It was weak and I was like kept doing it. Is it right? Or i should go somewhere to let them fix it. Im just afraid that Im not doing it right, im just 17 i don't know what im doing hahaha help please