If i feel someone is depressed, what shall i do?

Open dialog: Try to enter into a conversation with them and ask how things are going. People often need to share their feelings and how they are doing. Use open ended questions. Ask "how are you feeling" "don't you seem to notice a lot of depressed people these day?" and such, to lead you into having them open up to you. Then be supportive and maybe suggest they see a mental health professional. B suppo.

Depends: If "someone" is a person related or very close to you, ask discretely about their mood, suggesting they visit their doctor if they are excssively sad or depressed. Offer to accompany them if needed to their doctors visit. Try not to be an "amateur" psychologist with them. If they are suicidal, contact their family or 9-1-1.

Suggest evaluation: Suggest to the person that you are concerned about to make an appointment with a psychologist (counselor) or psychiatrist. Either specialist will be able to tell if the patient needs counseling and/or medication due to a chemical imbalance.