Can I grill a chicken/turkey breast in the night and eat it 12:00 and 18:00? First of all, I'm sorry for my English, I'm not fluent.

I'm on a diet where I can eat only chicken breast and ground muscle (don't know the right word for this but I tried) as the meat (and fish, but I don't like it). Since I work like 10 hours a day and I don't come home for lunch, I have to take my food to the work. So I usually cook the meal at night and I have lunch for like 2 days.

But when I tried to grill the chicken, the taste wasn't very nice. The only condiment I'm using is salt. So, here is my question: can I grill a chicken breast at night and eat it at 12:00pm and 18:00pm? Are there any risks of getting food poisoning or something like that?

BTW, can someone give me some tips about maintaining the chicken/turkey breast in the refrigerator (and not in freezer)?
Any kind of cooked meat or fish and most perishable foods in general are safe as long as they are fully cooked and refrigerated within 2 hours (although the quality will deteriorate rapidly with fish).

If you plan to eat the leftovers twice then refrigerate two individual portions. Reheating the same item multiple times raises the risk of bacterial contamination. That is really the only thing you need to concern yourself with for short-term storage.

For more information see the USDA Basics for Handling Food Safely.