Of course, the best thing to do for this is to read the Quran or Hadith. I would also suggest reading a biography of the Prophet, peace be upon him.
Out of the biographies that I’ve read of him, my favourite is Muhammad (peace be upon him) by Martin Lings for a number of reasons.
First of all, Lings cites the Quran and Hadith every time he makes an assertion about the Prophet (peace be upon him)’s life. As such, there is evidence behind all of the statements Lings makes.
Second of all, Lings storytelling skills are above par; the reader is hooked from the first page. The following excerpt is about the conversion of Umar (may Allah be pleased with him) and is a great example of Lings’ captivating writing style:
There was no question of 'Umar's keeping his Islam secret. He wished to tell everyone, in particular those who were most hostile to the Prophet. In after years he used to say: "When I entered Islam that night, I thought to myself: Which of the people in Mecca is the most violent in enmity against God's Messenger, that I may go to him and tell him I have become a Muslim? My answer was: Abu Jahl. So the next morning I went and knocked at his door, and Abu Jahl came out and said: "The best of welcomes to my sister's son! What hath brought thee here?" I answered: "I came to testify to the truth of that which he hath brought." "God curse thee!" he said, "and may His curse be on the tidings thou hast brought!" Then he slammed the door in my face."
Also, not only does Lings write about the life of the Prophet (peace be upon him), but he also writes about the history of his ancestors from before he was born, and his descendents after he passed away. He also discusses religion before and after the life of the Prophet (peace be upon him).
As such, for anyone who hasn’t read this biography yet, I would strongly suggest that you pick up a copy and start reading!