Hello,
Welcome to healthcare magic.
For prevention of migraines and cluster 
headaches, it is advisable to identify the triggering factors. Sunlight, hunger, mental 
stress, premenstrual tension, strong odors, physical exertion, irregular bowel habits, certain foods are all known to trigger migraines. You need to identify the triggering factors and avoid them. 
Try to maintain a healthy lifestyle , eat a well balanced diet rich in fiber, exercise regularly, drink plenty of water everyday.
Try 
yoga and 
meditation including breathing exercises called pranayams which will help your overall health. 
As far as medications are concerned , you can try prophylaxis with amitryptaline after consulting your doctor.
For your 
GERD, in addition to the above lifestyle measures, try to have smaller meals at frequent intervals. Do not lie down immediately after meals. 
Avoid spicy and fried food. 
Hope this helps you.
Wishing you good health.