If you are thinking to purchase so purchase from trustbe sites and big compnies and good brands only like amazon, Flipkart, Snapdeal, abof, bewakoof.com and many more.
If you think someone can steal your informatio so do shopping and banking in private browser.
Always use virtual keyboard while transferring your fund.
Use beest antivius and paid version for safety.
Never believe on pop up windows.
If you see any virus detct image so never believe on that image.