I agree with others, Outlive is worth reading. It can get a bit deep in the weeds at times but overall it simplifies a subject many find complex and is highly actionable. I think the general themes of healthspan have been covered already but I'll try to expand a bit on two:
1) The importance of high quality sleep has been discussed. Caffeine (half-life of 5-6 hours) and alcohol really negatively impact sleep quality. You may sleep plenty of hours but they will inhibit you from getting into the much needed "deep sleep" state. I try and avoid caffeine consumption after noon and consume alcohol 1x weekly knowing my sleep will suffer. I'm not about to start watching NU football sober.
2) Move more frequently. I exercise 6x weekly but can be pretty sedentary otherwise. While this isn't terrible its also not optimal. Below is a brief video that makes a case for short bouts of movement throughout the day. These are really easy to accomplish.