I personally don't believe undoubtedly/wholly all that I hear, read and see. And you too shouldn't believe undoubtedly/wholly all that you hear, read and see. Listen up, the only thing you ought to believe undoubtedly/wholly is nothing else but God/the scripture. Because, come what may, God/the scripture has never been broken and it cannot be broken by anyone/anything scripture reference (John 10 : 35). So, feel free to believe God/the scripture undoubtedly/wholly. For, even the grass withers, the flowers fade but God/the scripture stands forevermore, scripture reference (Isaiah 40 : 8). Oh! Yes, God and his words are ever infallible. Besides, God respects his word i.e. (the scripture) above/more than his name. That infers, he (God) can/will go extra mile just to ensure that his words/promises for you will come to pass. Therefore, do believe in God, his promises, words and the scripture undoubtedly/wholly. Because, you can't/won't be disappointed for believing in God, his promises, words and the scripture.
Emeasoba George