If you want to improve your life, but your mental health and energy levels are too low to exercise, start with hygiene.

Take showers every day, continuously lowering the water temperature. Use dental floss and tongue scraper. Brush your teeth twice a day. Wash your face every morning and every evening. Use evidence-based skincare products: adapalene, panthenol, SPF 50+ sunscreen. Keep your toes and nails tidy. Shave routinely.

According to Nadya Tolokonnikova, a prominent Russian dissident who was imprisoned, denying basic hygiene is a _very_ efficient way of breaking someone into submission that is often applied to dissidents in Russian prisons. So, doing a reverse of that should improve mental health.