Islam is a universal religion decreed by the One True God (Allah in Arabic). Islam simply means submission to the Will of the one true God (Allah), the Creator. Since the rise of Islam, there have been endless challenges, attempts, allegations, and plots to stop its spread or to distort its image and make people hate it or run away from it!
The main message of Islam is the same basic message in all revealed religions, as they are all are from the same source, and the reasons for disparity found between religions.
The Day of Judgment day will be the beginning of a life that will never end. On that day, all people will be rewarded by God according to their beliefs and deeds.
The Quran is the final revelation of Allah to all of mankind, which was spoken by Allah the Exalted Himself and conveyed through the Arch-Angel Gabriel in Arabic to the Prophet Muhammad, in sound, word and meaning.
The first thing to do is have a proper attitude. In Islam, "deeds" mean actions and spoken words, and that includes attitudes. Passing thoughts are not accountable.