I think the best chest exercises target the upper chest.
The upper chest gives that heart-shaped line when wearing a tanktop. Also, the upper chest is the hardest to build. The middle of the chest benefits from upper chest workouts. Try not to do too many or any declines as they will pull your nipples down and give you a breast-like appearance. Also be careful of dumbell flys because if they're not done properly they can easily damage your shouldersThe Athlean-X Channel has great alternatives for upper chest isolation.