Complex sentence: In 2008, he joined the the U.S. Army and did one month of basic training at Fort Jackson, South Carolina before being discharged for "failing to meet the minimum administrative standards".
Split into simpler sentences: In 2008, he served in the U.S. Army and was stationed at Fort Jackson, South Carolina, for one month. He was discharged before he could complete basic training for "failing to meet the minimum administrative standards".