I have been diagnosed with sever focal stenosis with claudication in my left superficial femoral artery. what can be done to improve this condidtion?

Vascular disease: You need to be evaluated by a vascular physician who could be either a cardiologist with peripheral vascular sub-specialty or a vascular surgeon. You're describing symptomatic type of peripheral vascular disease and there is a risk of progressing to limb ischemia and complications. Should you develop any left leg pain at rest, coldness, or loss of sensation/numbness, then you should go to the ED.

Be reassured!: Most patients with claudication do well for a long time. NEVER smoke. Aspirin & statin daily unless good reason not to. This slows plaque growth. Leg exercise & med called cilostazol can reduce symptoms. If claudication really impacts lifestyle angioplasty or bypass surgery can relieve symptoms. Procedures optional unless wounds or skin breakdown on feet. Dont be scared into unnecessary procedure!