What do you do with that uninvited guest on your forehead that stands out especially under the transparent winter sunlight?

How do you all calm your skin when it suddenly turns red? This morning, I looked in the mirror and saw a huge, red pimple in the middle of my forehead. I can't help but feel frustrated, whether it's the cold winter air or the stuffy indoor heater. The sunlight outside the window is unusually clear, creating a stark contrast, making me feel gloomy. Honestly, I've been wondering if my recent habit of not drinking enough water and staying up late is showing up on my skin. The cold weather makes me curl up all the time, and my skin feels dull and sensitive, making it almost scary to look in the mirror. Rather than simply applying expensive ampoules, I'm trying to gradually rebuild my daily routine. What do you consider the most important routine during this dry season with such large temperature fluctuations? Even something as simple as keeping a humidifier on 24/7 or drinking warm tea frequently would be great, but please share some wisdom with a "winter skin nomad" like me. Every time I see a pimple on my forehead during these lazy afternoons while waiting for lunch, I sigh deeply...