I want to sell public database by making website

Hello I am planning to make a website on which i am going to sell database of people around india in excel sheet including their phone no. , Adress , age , name etc So i am little bit confused that selling these type of data is illegal or legal i have listen somewhere that it is illegal But on other hand many websites are selling these type of data file openly on there website anyone can purchase that after doing a payment So tell me this is legal or illegal first thing Second thing i want to know If this is legal Then after making a website and providing database to customer in lot of quantity , can i purchase from others website and resell it on my website or not Can i do this or not I am asking this because from which website i going to purchase these data it is clearly mentioned on there website terms and conditions page that "THE USER shall not sell or transfer THE DATABASE to any other person/company/body corporate without obtaining authorisation of THE COMPANY and any such use without authorisation shall be ILLEGAL and THE COMPANY is entitled to take appropriate LEGAL ACTION against such USER. " So is it wrong thing to resell there file or not If it is wrong then how they claim there ownership to that particular excel file Because it is just an excel file nobody claim that it is mine or others