hello, your brother is having early lumbar spondylosis
that is the intervertebral disc
is pressing on his nerves which is causing the pain. There is a chance for conservative management also that is with tablets, injections and physiotherapy
he can improve and he should do back strenthening exercises which he has to contine and maintain correct posture while working on computer and avoid using laptop and take a break every 1/2 hr of sitting in the same position. so please consult a neurologist
and physiotherapist who will guide and i dont think there is need of surgery immediately.