I give my baby some steamed mashed apple.. even on giving it for the fourth time he does like taking vomit and only then pushes to his throat..does this mean I should stop giving apple now ?

No you should surely try. However try another fruit and try apple after a couple of days. You can also mix apple in another fruit. Since this is the first food you have tried it is also possible that the baby does not know how to deal with the different texture.