I want to wear contact lens, is it safe for me?

There is nothing to do with your age when comes to the safety in wearing contact lens.
Your personal hygience habit plays a BIG role. You have to clean your hands before wearing lens. Clean and sanitize the lens facilities regularly. Better do not wear them overnight if possible to let your eyes breathe and relax.
Your eyes' physiology and eyesight determines which types of lens fits you right. Consult your eye care professional (ECP).
激光矯視(LASIK, Laser-Assisted in SItu Keratomileusis) is the most commonly performed refractive surgery procedure nowadays. Clinically it is an effective method in correcting eyesight problems. But the success is very much depend on the expertise of your eye surgeon. There are reported cases of lose eyesight due to wrong amount of tissue remove from the cornea by the excimer laser.
Again, it is not your age that tells whether it is safe to do a LASIK cure, but it is expertise of your ophthalmologist.
Click on the below link to see more professional details:

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