Complex sentence: He composed many operas, two symphonies, many songs, he was helped and promoted by Mahler and Bruno Walter, a close friend of Erich Wolfgang Korngold and Franz Schmidt and was regarded as an Austrian master by his contemporaries.
Split into simpler sentences: He composed many operas, two symphonies, many songs and was helped and promoted by Mahler and Bruno Walter. He was a close friend of Erich Wolfgang Korngold and Franz Schmidt and was regarded as an Austrian master by his contemporaries.