Itchy Skin, Find a Solution

As the chilly, dry autumn season begins, I've been experiencing unbearable itchiness all over my body, especially below my belly button, on my thighs, and on my back, and it's been so hard.
At night, I often have trouble sleeping, and I unconsciously scratch my skin, which turns red and even causes wounds.

It is not clear whether this type of itchy skin symptom is simply due to dryness or an early symptom of another skin disease (e.g., psoriasis, atopy, etc.).
What are some self-care tips I can try right away to help relieve this itchy skin?
Specifically, I would like to know if there are any tips that can help reduce itchy skin in daily life, such as shower habits (water temperature, shower time, whether or not to use soap), criteria for selecting moisturizer, and methods for managing indoor humidity.
Also, I would like to know what methods are available to treat this itchy skin symptom.
I want to enjoy a comfortable autumn free from this annoying itchy skin.