Complex sentence: Niebeling developed an interested in modern art, classical music and theatre, but was unable to study acting for financial reasons, and therefore enrolled in a business degree at the Mannesmann-AG in Düsseldorf.
Split into simpler sentences: Niebeling developed an interested in modern art, classical music and theatre. Although he wanted to, he couldn't start studying acting for financial reasons, and therefore started a business education at the Mannesmann-AG in Düsseldorf.