They all must work together for you to truly be fit.
Move daily. In all planes. With resistance. Make it fun.
Eat mostly Whole Foods. Lots of protein, fruits, veggies and water.
Prioritize sleep. Both quality and quantity.
Not all stress is bad. Keep the good stress (the stuff that pushes you to grow and get outside of your comfort zone.) Minimize the bad stress (the kind that makes you want to rip your hair out.)
All of these pillars matter. Assess them and improve where you can.
Have fun with it, too.