We have not learned everything about human body. We get closer and closer to unlock what our body can do. Our human body is limited on what it can do by nature. That hasn't stopped science. We continue to learn new way to ward of disease. We continue to learn how strong we can really get so yes human can unlock rapid cell regeneration.
So scientists have isolated the gene responsible for cellular regeneration. The issue comes into play when they mess with the actual gene. Modifying the gene and activating on demand is one problem. Another problem is the fact that this gene when activated would begin regenerating cells rapidly creating tumors ergo causing cancer. Hopefully one day they'll be able to activate the gene on demand to rapidly regenerate cells, tissues, organs, and entire limbs.
I can do this power slowly indeed you can heal slowly for example you are cutting your finger part it is not re grow but you try for healing and two days later your finger part can heal that it everyone can do this ability with techniques ok just techniques