What's the difference between Tibetan Buddhism, Southern Buddhism Buddhism and Northern Buddhism?

Tibetan Buddhism: It is distributed in Tibet, Qinghai, Inner Mongolia and Sichuan. Mainly studying the classics of the Ministry of Secret Education.

Southern Buddhism: Distributed in South Asian countries, Yunnan and Guangxi in China. I mainly study the classics of the Ashan system.

Buddhism in China: mainly distributed in China, Japanese and Korean. Just learn the Mahayana classics.