So my question is if taken a 4 months plus and it is negative can it turn positive at the 6 months mark which is additional 2 months?

Unclear question: If you are asking about HIV test, a 4th generation is generally reliable at 4 months after exposure. Just to be sure, you should get a HIV nucleic acid test at 6 months after exposure. Have a healthy diet, exercise 30 minutes/day, drink plenty of water daily so your urine is mostly colorless, have safe sex, no tobacco alcohol weed or street drugs. For nutrition: http://www.choosemyplate.gov/.