Llama is the correct term for the large, domesticated camelid native to South America.
Lama refers to a Tibetan Buddhist monk, a spiritual leader.
Here's the information about a llama's size:
* Height: 3.5 - 4.5 feet tall at the shoulder
* Weight: 280 - 450 pounds
So, the average size of a llama is about 4 feet tall and 365 pounds.