A:AnswerConfused why anyone would buy a pre-built just to basically build it again. But, it looks like a mid-tower sized case and micro-atx motherboard, nearly any mid-tower case will work. Measure it.
A:AnswerPics too small to tell if there are multiple lights, some mobos have multiple diagnostic lights. It's likely a generic "failed to boot" light, if you don't have experience working on PC's, bring it back and get one that works. If you know how to SAFELY remove and re-seat the graphics card and RAM, I would try that first. Check power connections too.
A:AnswerThank you for reaching out to us. The manufacturer, model, and specifications of the components included with this system may vary depending on what was currently available at the time the PC was built.