I am going in for a blockage on my right kidney i am stage 4 renal failure w/ coranary artery disease and am going in for a surgical procedure remove a 60% blockage on my right kidney and 2 large stones on my left how serious is this procedure

Although : Although nothing is without risk, removing kidney stones is a fairly minor procedure these days. Most urologists will use lithotripsy to break up the stone, or do a cystoscopy (look up from the urethra into the bladder and ureter) and use some mechanical way of extracting the stone). By "60% blockage on my right kidney" i'm assuming you mean a kidney stone blocking the urine outflow. Because repairing a blocked blood vessel to your kidney is a somewhat more complicated surgery, and my previous advice does not apply to a vascular repair of your kidney's artery.

Very important: Most important is to understand that with stage 4 renal failure and coronary artery disease you are fairly likely to develop kidney failure in the future. The question is how long. Your job is to address factors in your control such as weight, blood sugar, blood pressure, medications, smoking. The procedure sounds like it is not "open", and will use balloons + lithotripsy. Some risk but reasonable.