Traveling Through the Timeline, as a Child, How Should I Save Others?

The story of Shinichi traveling through the past to save Yi Yuan is a bit of a new plot. He decided to cut his own legs after all the updates he followed were discontinued. The whole story is full of fabrications, and there is a high probability that the characters are OOC. There is also a one-sided original character who is obsessed with the protagonist. I just like this old-fashioned plot, so I guess it is a cool story, but there is no way to guarantee that the original character (red party) will definitely not die. As for the original characters, there is a high probability that they are background boards, so it is normal for a death plot to occur. Purpose: Save yourself first when saving others