PAD and renal fail. A blockage in the artery that supplies blood to a kidney can diminish the kidney until it is irreversibly damaged. Hypertension and diabetes when out of control can accelerate vascular disease and kidney damage. So yes, pad/ peripheral artery disease can cause or accelerate kidney disease.
Hard to tell. Kidney failure, in and of itself, doesn't directly cause any vascular conditions, however, it is a rare stand alone condition. It is usually caused by chronic diseases such as diabetes and/or hypertension, heart failure etc. Those conditions, in turn, can lead to vascular complications, such as stroke, heart attack, gangrene etc. Disease of kidney vessels (narrowing) may also cause kidney failure.