Hello dear,
Since your friend has a very high power of glasses, Lasik treatment shall not help her as Lasik is done for maximum power of 10. Beyond that other options are there like placing an additional lens inside the eye (along with natural lens) called as ICL.
Next Steps
Meet a refractive surgeon and a retina specialist.
Health Tips
People with very high power are prone to having other eye problems, which may increase sometimes (and may also lead to vision loss) if not checked before surgeries for laser or glasses removal. Do get yourself checked by a Retina specialist to rule out other eye problems even if you do not plan for a surgery.