Maddox Jolie-Pitt, who turns 18 Monday, is set to start classes at South Korea’s Yonsei University where he will be studying bio chemistry, a source exclusively tells PEOPLE.

“He got accepted to other universities but choose Yonsei,” the source says. “He has been studying Korean language. He has lessons multiple times a week to prepare.”

And the oldest in the Jolie-Pitt clan is starting classes this month, with Jolie, 44, making the trip to help him get started.

“Mom is dropping him off in August,” the source says of Jolie. “She is very proud. She will miss seeing him as much, but he’s ready.”

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The source adds that while he’ll be far away from their American home base, his new school is close to the family’s Cambodian home.

“He’s very close to his siblings and they all hope to visit,” the insider says of Pax, 15, Zahara, 14, Shiloh, 13, and 11-year-old twins Knox and Vivienne.

Jolie previously opened up to PEOPLE about Maddox’s college plans, saying that she was “nothing but proud.” PEOPLE in the

“I look forward to all he will do,” the actress added.

Maddox’s choice to attend a South Korean school comes after he was spotted visiting universities there with Jolie back in Nov. 2018. The two visited campuses in Seoul while Jolie was in the country on an official visit as the United Nations High Commissioner for Refugee (UNHCR) Special Envoy.