How can I regain my eye sight as it used to be before I started wearing spectacles?

OK,is there any way to like,get back your original eyesight level,after you started using specs?Right now,my power is around 300 on both eyes,do you think there's anyway to possibly get it back to 50 or less.My friend says,I have to use 'the laser' to shrink my eyeballs to its original size,since I'm short-sighted.Thanks for answering.

The clarity we can get through artificial corrections(glasses, contacts, lasik) is the minimum vision we can obtain with our unaided natural vision system.
Most people can obtain natural perfect eyesight by unlearning the incorrect vision habits, reintegrating the correct vision behaviors, and undoing the damage of artificial corrections(glasses, contacts).
Natural perfect eyesight is: effortless, amazingly clear, three dimensional, brite, very sensitive in the dark, and activates memory and imagination. Eyesight through increasing glasses(contacts) is dim, two dimensional/flat, strained, diffused, night blind, staring, face freezing, neck locking, memory and imagination stunting, squelches breathing, promotes poor posture, introverting, etc.
The best ways to learn about natural perfect eyesight are to delve into the best books and learn from the best teachers. If anyone talks about eye pushups/drills or corrective hard lenses avoid them, don't waste your time.

People's eyesight changes naturally, but it's unlikely to improve that dramatically I'm afraid. There's not anything you can do to help it either. Laser surgery would correct it (if you're a suitable candidate), it removes a part of your eye, rather than shrinking it.