Hi Utkarsh, you can use JS Executor to execute JS script method window.open() to open a new tab in browser using Ruby. Following code shows how you can open new tab in a browser:
require 'selenium-webdriver'
driver = Selenium::WebDriver.for :chrome
driver.get 'https://www.google.com'
#Open a new browser window
driver.execute_script( "window.open()" )
#Use the newest window
driver.switch_to.window( driver.window_handles.last )
driver.get 'https://google.com'