"Powered On" Do you mean you 'see' your desktop & app icons? If that is correct your internal display assembly has a problem.
Can you give us your exact model by looking up here: EveryMac - Lookup. Plug in your systems serial number which can be found under 'About this Mac'
Once you know paste the systems URL here so we can correctly identify what you'll need to do to fix your system.
Here's the IFIXIT guide to replace the display assembly for your system: MacBook Pro 15" Retina Display Late 2013 Display Assembly Replacement and here's the needed part: MacBook Pro 15" Retina (Late 2013/Mid 2014) Display Assembly - Apple P/N 661-8310. IFIXIT only has two B quality (used) in stock presently.