Hey Paula, to get the tagname of a particular webelement, you can use getTagName() method. This method don't take any parameter and return the tagname of the specified element. Following code sample will return the tag name of textbox element:
WebDriver driver = new FirefoxDriver();
driver.manage().timeouts().implicitlyWait(60, TimeUnit.SECONDS);
driver.get("https://edureka.com/");
String TagName = driver.findElement(By.id("TextBox")).getTagName();