OK. Before immediately diving into the deep end of the OSLO pool, we'll swim in the shallow end for a bit. This means that you won't need to learn any new engineering or physics, just the OSLO software program.
The basic problem is to ray trace an image through a biconvex lens. The focal length of the lens is 50mm and the image is 100mm from the lens. This is a 4f system and the result should be a familiar paraxial raytrace: the intersection of the two blue rays determines the image plane.
We want OSLO to trace rays from the top and bottom of the object. The figure below demonstrates that the paraxial approximation is pretty poor for this case!
OSLO requires a complete description of the optical system as a series of numbers. Finding and entering each number is simple, but they all must be done correctly (because OSLO does not award partial credit). The task is made complicated because OSLO's terms have precise meanings that might differ from yours.
The basic inclination of most students who are asked to solve a problem with OSLO is to immediately start entering numbers into the Surface Data window and then becoming frustrated because nothing really works. I am sure you're not one of those students.
The first few times that you use OSLO, I suggest that you labor through ALL of the steps below. Once you become more familiar with OSLO the entire sequence can be reduced to just the initial sketch with jotted notes. The steps are