Is there any way i can prevent getting alzheimer's disease if it's hereditary?

No: But staying healthy by keeping BP and cholesterol normal as well as being physically and mentally active can help in delaying the process. Entering clinical trials for new drugs and preventative regimens are other options. Even if there is a strong history of ad in your family , it is unlikely you are 100% sure to get the disease. The familial type of ad is very rare and presents very early age.