If your goal is to do some writing every day, invariably, just like with exercise, one day you'll wake up fatigued. Only when the muscles are sore after long days of exercise and by simply being sore stop you from moving, quite often your brain isn't capable of stopping you (my case), and as part of your writing routine you need to learn to recognize this fatigue. To learn to stop. To learn to give your brain a rest.
And it really does need rest, to recharge.
Not to write something else.
Not to read something.
Not to engage.
But simply be still.
That means you'll have to train yourself to leave your writing cave without your phone (oh horror!) and go wandering about without any clear aim. Ideally, you wander somewhere in nature where you can't get distracted from doing nothing. Do it until you get tired. Get home. Nap. Continue doing nothing. Maybe cook some food, slowly. Eat it, slowly. Luxuriate in this.
The next day you'll wake up with twice the energy. Or maybe it'll take you several days.
This rest is so important. It'll carry you through a long career of writing without burning out and giving up (easy for me to say—I still struggle with this, but I'm getting better).