Dear dr, what kind of antibiotics are suggestible for tongue infection at the age of 11 yrs?

None. Sores on the tongue is only rarely caused by bacterial infection in immunocompetent individuals. Frequent use of mouthwash will be of help. Occasionally, a short course of steroid can result in fast relief.
Need more info. This requires an examination of the 11 year old to determine the type of infection and its likely cause. Antibiotics should not be used without a very good reason as their complications may create more problems than they solve. Hope your 11 yo. Is better soon.