No grease is applied on chains of most bikes sold here moreover if any is applied its contaminated with fine dust partials which acts as a abrasive.
Best is to dip the chain after washing thoroughly with petrol in thick gear oil and warm it slightly or let it in sun light for few hours so that it pemetrates fully in all cavities then take it out and let excess oil dribble out of it and use it . and it's recommended to remove the chain from bike for doing so.