Force Fins What Is The Difference Between Force In And Force Out (mechanical Advantage)?

What is the difference between Force in and Force out (mechanical advantage)? - force fins

I am looking for the effect of mechanical physics
But I still can not understand yet what is the difference between work and work in the

eg. A force of 100 N is applied with a lever. This force lifts a load weighing 275 N
Fin and Fout it?
is 100N = End
275N = Fout