My mom has very bad vision. she is 63 with glaucoma and almost went blind if she didn't have surgeries for cataracts.how to prevent self from getting?

Preventing glaucoma: I know of no way to prevent glaucoma if you're destined to get it through genetic linkages to someone in your family. The best prophylaxis in my opinion is to have regular eye appointments where the pressure is checked and intervened on at the first sign of trouble. Otherwise, just good general principles of good health, exercise, healthy dieting/weight, check for diabetes, etc. etc.