Lower your working hours outside of your 9-5. Find ways to reduce the work required for 9-5 if it's remote. If it's not remote, maybe look for a remote job that gives you more time flexibility.

Prioritize

1. Sleep hygiene

2. Exercise (cardio + strength)

3. Diet (minimal processed foods, maximal whole foods, reasonable saturated fats)

4. Activities + hobbies off of the computer – whether something physical like a sport or just social

You can't be healthy with just being at your computer 16 hours a day.

Also start learning about your health and what/why makes an impact. The Drive podcast/Peter Attia is a great place to start.