Laptop start up

Hello,

My laptop keep saying it ran into some problems and it's been saying preparing problem disk or rather repairing problem disk.... Something about error disk, what could be wrong?

It's been two hours and I'm still waiting for it to start up. It went to the code area where I entered the code and it never fully start up....

I'm trying the 12 steps by have only been able to reach step 5.......

What do I do... I need my laptop

Help me

Dione