Hello Nitish,
To become a police inspector you have to go through your high school , intermediate and graduation too. After graduation you need to clear CGL exam through which you will get a selection for SI post and further you get permotion based on your performance.
Now coming to your second question daroga is a lower rank post whereas inspector is a high rank post in police department.
Hope it helps.
Thank you :)
Now coming to your second question
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