It seems like your laptop is booting up in BIOS. Please do try these troubleshooting steps that may help in solving the issue.
- While in the Boot/App menu press F9 to set its default then press F10 to save and exit.
- If it will not load Windows do a hard reboot, remove the battery and unplug the AC adapter then press and hold the power button for 20 seconds then try booting it up again.
- If it will still not work remove the HDD off the laptop then boot it up and see if it will load into a black screen with an error about missing boot device which means that the HDD if the suspect.
- Put the HDD back in and see if the same problem will persist.
- If all these will not work and if the laptop is still under the factory warranty contact Lenovo for a repair.