Hello. Thank you for posting.
Kidney failure means that kidneys have failed and no longer work well enough to keep someone alive without dialysis or a kidney transplant. Kidney failure and renal failure mean the same thing—your kidney function is below 10% to 15% and you need renal replacement therapy to stay alive.
For most people kidney failure occurs after years of having chronic kidney disease.
More information here. Copy/paste: https://www.webmd.com/a-to-z-guides/understanding-kidney-disease-basic-information#1