It sounds like your computer is on, just the display isn't...
Try turning it off, connect an external monitor, turn on the external monitor and then turn on the laptop.
If you can see on the external monitor, then the attached display or the ribbon cable that connects it are your most likely problem.
If you can't see on the external monitor either, but are certain there are sounds within the laptop, then your graphics card/GPU is the issue and will need replacing (and possibly the motherboard will need replacing).