Yesterday I wrote about financial independence, link below. Part of being financially independent is being healthy enough to avoid spending a lot of money on prescriptions, doctor visits and medical procedures. Avoiding a list of chronic maladies that require a lifetime of management can come down to habits. The right habits and you can essentially opt out of all that and age successfully, doing what you want to an old age. This is called healthspan.
https://notepd.com/idea/what-is-financial-independence-qt7id
1. The best time to start
Like many things, the best time to start good health habits was 20 years ago. The second best time is right now. The body is very forgiving, you just need to start. Here is a news story about women in their 60's and 70's just starting to lift weights including deadlift and squat and all of the things they are reversing by doing so.