You need a detailed refraction testing first to ascertain the type and amount of refractive error that you have. It is possible to have a spectacle power in one eye only or that one eye may be more affected than the other. There is no eye drop to stop or reverse the refractive error. However, regular use of glasses, if required is important for keeping eye power stable. You can go in for contact lenses if you don’t want glasses. Once your prescription is stable, you can consider refractive surgery if required (after detailed ophthalmic evaluation).

Hi.. Better to get the eye checked and figure out the reason for decrese in vision. If it is power , then you have to wear glasses/ contact lenses or go for Refractive laser. Unfortunately,  there is no other way.