Hi there...excessive sweating will need complete evaluation like where is it more predominant, palms and soles, or forehead or whole body, does it increase with your nervousness? Also associated comorbidities like
diabetes can also cause increased sweating. You can try conservative measures like yoga, meditation, having bath twice a day initially. If no progress you can visit a dermatologist or general physician for further evaluation.
Feeling lethargic, tiredness could be due to low haemoglobin or diabetes or pcod. you will need to consult a physician for that.
Regarding pcod kindly consult gynecologist, they will be able to guide you regarding treatment.
Dark circles is usually hereditary. But sometimes can occur due to lack of nutrition or even in atopic cases. Visit a dermatologist for that. They will start you on depigmenting agents. Keep using sunscreens for now. And lastly you are 9kgs underweight for your height. Start eating healthy foods rich in proteins and fibres like egg white boiled chicken vegetables fruits pulses. Start exercising slowly.