Purchase train ticket leaving from Beijing West Railway Station at Beijing Railway Station

Hi. May I know, is it possible to purchase train ticket leaving from Beijing West Railway Station at the Beijing Railway Station?

In this case, I want to board train to Xi'an Shaanxi departing at Beijing west railway station. As my hostel is near to Beijing railway station, may I purchase it there?

If yes, is there any English-speaking officer at ticket counter and may I know which ticket counter and where to locate it?

Thanks