My hp computer/pc

[icyykikii]

Hello, I have had my computer for a while now. I haven't been on it for like a year because I was grounded. I tried to turn it on but every time I try it says "ERROR: no disk has been detected or the disk has failed" Ive tried and tried and it doesn't work. Ive even searched up videos to help me but does don't help either. My keyboard hasn't been working so every time I try to press buttons it just dont work. How am I supposed to connect my keyboard if my computer wont turn on? 

[WAWood]

I don't understand the keyboard issue -- is it wireless?  If so, you need to get a wired keyboard and connect that to see if you can then press F2 repeatedly when booting to get the diagnostics screen and run the diagnostics.