Projectile physical hit reaction

How would you implement physical hit reaction to a projectile hit on human mesh? I’m confuse, can someone help me with that?

a shell, if it is a bullet, can shoot a character (fly through), or get stuck in a bulletproof vest. In this case, the character must receive a return or blow in the direction of the bullet’s flight.
In the first case, the projectile flies further with a change in the trajectory and a lower speed.
In the second case, the shell seems to be destroyed.