No Crank, no start

So my car is having some issues starting, at first the battery light had come on. So I brought my battery into the Autozone near where I live, they tested the battery and it was dead. So i got a replacement for it, the car was fine and then started to do it again. I figured that the alternator was not charging the battery or I had a bad grounding wire. I went through the maintenance manual and found all the grounding areas in the engine bay, i cleaned them up and replaced the alternator, and got the belt tightened. upon doing so. The car wont crank, turn over, or make any noise when trying to start the car.