Hi,welcome to Xian. I am a local Xian. I advise you to come to visit Xian in Spring or Autumn as the weathere are more comfortable in the two seasons.
If you jion a tour, you can see more attraction in one day such as Terra Cotta Warriors, the City Wall and the Drum Tower. For two days, you may visit the Big Wild Goose Pagoda, Shaanxi History Museum and Tang Paradise apart from the places i have mentioned before in one day tour.
I find that there are many Xian tours(https://www.travelchinaguide.com/package/xian.htm) on this website. You can have a reference.
If you jion a tour, of course you will be picked up at the airport and return there.

While if you have a personal travel, you can just visit Terra Cotta Warriors and Horses in one day. The second day, you can go to visit the City Wall, Big Wild Goose Pagoda and Bell Tower.You need to deal with all the routes by yourself.

THANKYOU for your reply...when i land what bus can i get to teh terracota warriors and how long will it take?..

Do you mean from the airport to Terracotta warriors? Well, you have to take the shuttle bus Line 2 (about one hour) to Xian Railway Station firstly and then walk to the east square of the railway station. Here, you could catch bus 游5(306) to the Terracotta Warriorts directly in one hour.

Mr. Mike, if you speak the language you will have no problems going here or there by yourself. Mmm is different if you don't very few and far between speak english. You can't get directions. Organize your trip before you arrive. If you get a tour they will take care of you from the airport and back to airport and make sure you pass true security, then tour guide will leave. Been there, done that.