When you are applying force anything this thing apply this force on next surface . suppose you sit on a table it means you apply the force equal to your wait on the table and table apply this on the ground if the legs of the table are sharp pointed then the force is pointed on the sharp tip and it make hole in the ground but on the other hand if the legs of table is not sharp on that time legs not make any hole because the force is spread in the big area than sharp pointed leg same concept works in knife when knife is blunt yon need more force to cut anything because force spread in more area than sharp knife, sharp knife centered all the force on very small area and sharp knife cut anything easily
Pressure is inversely proportional to area i.e,if area increases,pressure decreases and viceversa.