Family history cancer stomach,colon,brain, breast and lung. most had. what diet or lifestyle recommended thank you?

The best advice is healthy living that includes no tobacco use, many fruits and vegetables, no processed meat, little or no alcohol, little as possible sugar or animal fat, keep a healthy BMI (18 -25), exercise regulary with at least 150 minutes of light exercise per week, avoid sun exposure and use sunscreen, vaccinate for Hep B and HPV, avoid risky sexual behavior and do not share needles.

If multiple family members have had various cancers of the mentioned organs, you may have a familial cancer syndrome, such as Lynch syndrome or one of its variants. You should see your primary care doctor, a gastroenterologist, or an oncologist for screening options. I certainly would not ignore this. You should get it checked sooner rather than later. Good luck.