Complex sentence: He entered Her Majesty's Consular Service in Japan in 1864, as a student interpreter, and was also a close confidante of Ernest Satow, the first British student interpreter in Japan and later British Minister in Japan and then China.
Split into simpler sentences: He entered Her Majesty's Consular Service in Japan in 1864, as a student interpreter. He was a confidante of Ernest Satow, the first British student interpreter in Japan and later British Minister in Japan and then China.