First, he was a brave soldier fighting against the Ottoman Empire. He was injured and went to Sicily to recover. In the meantime, he was promoted to Captain and intended to return to Spain but he was seized by pirates and ended up in Algeirs.
After five years, The Trinitarian Monks payed his ransom and he returned to Spain. So, his military career was burnt. He tried to go to Chiapas but His Majesty the King said "no".
Cervantes tried to be a playwritter -because they were like the movies nowadays (look at Shakespare!)- but no one could do anything against a Master like Lope de Vega. He wanted above all to be a poet and end up being one of the most brilliant novelist.
So, finally he wrote a text, Don Quixote. He was old, he was tired and he wrote the second part unwillingly: "he would never get to see how his work became one of the most important works in Spanish literary history".
He was a brilliant novelist but was determined to be a poet and failed as a playwright.