Hi,
If your seeing indicator lights on the laptop and the fan is spinning try and connect an external monitor if available to see if you'll get any display from it because if you do press the Windows key + P at the same time then select between "Display Only" and press Enter then see if you'll get your display back from the built in display because if you don't there might be an issue with it.
If don't still see any display from the external monitor when connected do a hard reset, remove the battery and AC adapter then press and hold the power button for 20 seconds then try powering it on again. If doesn't boot up last thing you'll need to do is to reseat the RAM. Remove them off the laptop for couple of seconds then just put them...