Some thoughts I had about how "saving" would work in real life

Two ways I thought of:

1: A person has the ability to "save" in real life, and the person is currently in Universe A. The person is about to die somehow, but a long time beforehand the person saved. Every time this person saves, another universe is made, hereafter referred to as Universe B, which is the exact same universe as Universe A. Both of these Universes have the exact same physical appearance, the exact same events that happened in the past and events that will happen, exact same people, etc. When Universe B is created, time in that universe is paused until that person gets transported into that universe. So once the person dies in Universe A, the person is automatically moved into Universe B at the location the person saved at in Universe A. This person has knowledge of what will happen, so then the person can somehow avoid the death using the knowledge of what happened in Universe A. However, since the person transitioned into Universe B, that person is still technically dead in Universe A, but alive in Universe B.

2: The same person has the ability to "save", but instead of making a universe time rewinds quickly back to where the person saves. The rewinding effect is noticed only by the person with the saving ability, and not to anyone else.

Of course this is completely fictional, and as a matter of fact it's probably inaccurate due to the fact it was not deeply thought of.