Mri shows foraminal stenosis l5-s1, l4-5, l3-4 and extrusion nearly abuts the descending bilateral s1 nerve roots. L leg is numb & painful. Surgery?

Would Need More Info. In general, i would need more symptoms, but what you are describing with your symptoms and the results of the mri, i would first recommend physical therapy and epidural before considering surgery. Really depends on your examination and whether there is any weakness. I would check with your doctor.
Surgery Last Resort. I would consult a fellowship trained spine/pain specialist to see your options. You may need surgery or you may not. If you haven't tried epidural steroid injections first, that may be your best bet first.