On the Virgintrains.co.uk website trying to select a arrival train station
In my Code I am able to select the departure location and in the next field I would like to se
You are trying to send a Tab press to null elements. Instead of separating the location and the tab key press, put them on the same line:
textBoxDep.sendKeys("London Euston" + Keys.TAB);
textBoxArr.sendKeys("Manchester Piccadilly" + Keys.TAB + Keys.TAB);
Also, Thread.sleep is not suggested. You can use a wait for a specific condition before proceeding instead. More info on waits here: https://www.toolsqa.com/selenium-webdriver/wait-commands/