Schilling's screen acting debut was in 1996, when he, aged 14, appeared in the Sat.1 TV series ‘Hallo, Onkel Doc!’ He was later cast in the theatrical film Schlaraffenland (1999) where he played alongside Franka Potente, Daniel Brühl and Heiner Lauterbach, but the breakthrough for him came with his performance in Crazy (2000, directed by Hans-Christian Schmid), for which he received the Talented Young Actor Award of the Bayerischer Filmpreis.

In the critically well-received 2004 film Before the Fall (German title: Napola – Elite für den Führer, directed by Dennis Gansel) he played alongside Max Riemelt a young and fragile student at a Nazi elite school (Napola). In 2006, he received a scholarship for the Lee Strasberg Institute in New York, where he studied for half a year. In the same year, he became a father to a son. Schilling was later given the role of the young Adolf Hitler in Urs Odermatt's 2009 film Mein Kampf (the UK DVD release is marketed as Dawn of Evil: Rise of the Reich), co-starring Götz George.

He originally wanted to become a Painter and study art after school. In a 2008 interview he said he was not much of an extrovert, and that, to him, having to deliver oneself up on a day-to-day basis was a major disadvantage of the acting profession.

In the early summer of 2014 his second child, a son, was born - the first child for Schilling and his partner, the assistant Director Annie Mosebach. In January 2017, his first daughter and third child was born - the second child by his partner Annie Mosebach.