my son 27 months old talks only very few words and speaking some jargon. he is unable to make sentence. what should I do

A. Hai good evening !! check other milestones,gross,fine motor skills are upto to age or delay. By 2 ,2.5 years age babies can able to speak sentences can respond ,can start conversations . As baby is having speech issues (delay in speech) go for assessment with Developmental paediatrician or speech therapist.