I have food poisoning, no vomiting mild diarrhea and fever iam 17year, 170cm, 55kg what antibiotic should I use and can I use it with metronidazole?

Not Food Poisoning. What you describe does not sound like food poisoning. It sounds more like a mild virus and no antibiotics will help. An OTC probiotic or yogurt and bland foods could help get you back. Either way if not better in 2-3 days, see your MD.