Not just I, but millions of people believe Jehovah is the only true God, and Jesus Christ is God's Son, not God. (John 17:3) Many of Jws were formerly members of other religions, including all those you mentioned. They individually carefully studied what the Bible really teaches, as opposed to what the churches claim it teaches. Based on that careful examination of the Bible, they became convinced that the Bible is God's Word and the source of the truth. Jw.org is the official website of Jehovah's witnesses, and contains information relating to the Bible in over 700 languages.