help me understand my fiance's situation

my fiance has a severe back pain. The MRI result was as follows: "There is a posterocentral disc herniation at L4-L5 and posterocentral disc protrusion at L5-S1 indenting the thecal sac and mildly adjacent nerve roots, associated with mild thichening of the ligamenta flavae". He is only 25 years old, he used to work in a airconditioning that required a lot of effort. Now he quit his job, the doctor gave him Difen-B12 which contains diclofenac, and selektine meloxicam, and an air pump back belt. He didnt benefit at all, pain persisted and many times it is progressive.
i need to understand the MRI result and what treatment should now follow? does he need a surgery? thank u in advance