Hi Meenal, you can use executeScript() method of Javascript Executor to open a new tab in existing browser:
driver = new ChromeDriver();
driver.manage().window().maximize();
driver.get("https://www.google.com/");
String link = "window.open('https://www.edureka.co','_blank');";
((JavascriptExecutor)driver).executeScript(link);
Thread.sleep(5000);
ArrayList<String> tabs = driver.getWindowHandles();
driver.switchTo().window(tabs.getIndex(0));
Hope it helps!
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