True! Creatine is an amino acid which is broken down into creatinine and used, similar to calories.
Creatine is synthesized by our body, it's not an essential amino acid. Liver, kidneys, and pancreas create creatine.
That's mostly true! However, like creatine, cholesterol is fully synthesized by our bodies. We produce all the cholesterol we need, there's even evidence that dietary cholesterol has very little impact on blood cholesterol.