My son is 2 years and 5 months old but not started to talk fluently... says appa Amma,akka n some more words...he follows what we saying but not trying to say it....what can we do further either to consult a doctor or not..?

Every child develops at a different pace. Many children speak pretty fluently by 2 and a half years and some don't. Even my son could not communicate fluently till about 4 years of age. Do not panic at the moment. Converse more with him and encourage him to give you answers. Slowly he will pick up the pace.