@Rakesh kumar , Welcome to Microsoft Q&A. you could try the following code to download file to specific custom folder by using selenium.
var options = new ChromeOptions();
string downloadFilePath = @"E:\Test";
options.AddUserProfilePreference("download.default_directory", downloadFilePath);
options.AddUserProfilePreference("intl.accept_languages", "nl");
options.AddUserProfilePreference("disable-popup-blocking", "true");
// declare driver with these options
var driver = new ChromeDriver(AppDomain.CurrentDomain.BaseDirectory, options);
driver.Navigate().GoToUrl("https://www.microsoft.com/en-us/download/details.aspx?id=25150");
var reportDownloadButton = driver.FindElement(OpenQA.Selenium.By.CssSelector("div[itemtype='http://schema.org/Offer']"));
reportDownloadButton.Click();
I used website instead of pdf, but they are fundamentally the same.
Website:
Hope the above code could help you.
Best Regards,
Jack