|Could we have the model number please?|
"how to reboot the laptop"
Do you mean factory restore? If so, see this for general information:
[reboot just means to power off then on again]
Not sure what you mean by "fires up". If you never ever see anything at all on the screen then it is most likely a hardware fault so factory restore will not help you. If it is hardware then it can be one of many possibilities, such as:
Screen or its connections
Internal component failure
When it is switched on try slowly lowering the screen, looking at it until it is nearly closed. If at any stage something flashes up on the screen then it is likely that the cable that joins the screen to the motherboard has worn due to hinging. The connections at either end have also been known to work loose.
Always pop back and let us know the outcome - thanks