Yes, it's important to wear sunscreen every day, even on cloudy or overcast days. Sun exposure can be damaging to the skin, and can contribute to the development of fine lines and wrinkles, hyperpigmentation, and skin cancer.
It's recommended to use a broad-spectrum sunscreen with an SPF of 30 or higher every day, even if you're spending most of your time indoors. If you're going to be outside for an extended period of time, be sure to reapply your sunscreen every two hours, or immediately after swimming or sweating.
Wearing sunscreen can help to protect your skin from the damaging effects of UV radiation, and can help to prevent a number of skin problems. It's an important step in any skincare routine, and can help to keep your skin looking healthy and youthful.