Hello I got a weird dry patch on my skin and the...

Treatment of dry bpatches on skin
Simple lifestyle changes can help Try to , avoid using hot water to shower , shower every other day instead of every day ,  use a moisturizing soap when you shower , apply moisturizer immediately after showering , avoid itching or scrubbing dry skin patches ,use a humidifier in your home , drink plenty of water and you can use topical cream such ass hydroquinone or by using chemical peels containing salicylic acid and glycolic acid , or by laser therapy
Diagnosis
by taking full medical history and doing clinical examination , and doind CBC to detect inflammation , and skin biopsy to detect the cause 
Causes

• Burns
• Infection
• allergies
• Hormonal changes
• Skin cancer
• Rosacea
• dermatitis
• Vitilligo
• Ulcer

Advice
you should followas these instruction and use moisturizer , if this fail , you should visit the dermatologist doctor to to examine you and giving a medical treatment regarding to your case