There are many anime titles out there focusing on what we would change if we’re given a second chance to relive our past. The best recent example that came to my mind is Boku Dake ga Inai Machi. ReLIFE carries a similar tone except it doesn’t emphasize too much on what the main character, Kaizaki Arata, would change when he was given the second chance to be a high school senior again.
Instead in ReLIFE, while also sorting out his personal issues, Kaizaki remembers to treasure the moments at what is his second time as high school senior.
Be warned though, from hereon there may be spoilers here and there.