How do nails attach to the nail bed?

So my toenail got bruised, drained fluid out, now like two-thirds of the upper right of nail isn't attach to nail bed (but left side is).





I read that the new nail growing will attach itself to the nail bed while the part unattached at the moment is useless.





So what makes the new nail growing attach itself to the nail bed? I'm worried it won't.How do nails attach to the nail bed?
Go to a foot Dr. and let him remove the left over piece of nail, it may stay and then new nail grow around it or over it and have a split in the new nail! It could really wind up more of a problem! Don't try anything yourself, you will wind up with a big swollen infected foot and have to go to the Doctor for a bigger problem then you have now! So go! Now--to the foot Doctor!