MY son is 3.8 yrs old, He is fussy eater, Suggest me how can I make him eat proper meal, Roti n DAl/Sabji?

Is it right to give pediasure to my son? He eats selective things, Like, Tomatoes, Cucumber, Popcorns, Chappati with cheese slice, or brown sugar, Rice with Brown sugar, Black gram,. Kidney beans, Etc, He likes milk very much, But does milk fulfils all his body requirements? He eats fruits too but I wanna him to eat three meals as we do with Roti, Dal etc