It's up to you

Hi I am an Algerian ,my cousin talk me often of you and your community and he explains me a lot of things like why we don\'t must to follow the sunnah . but me ,I have an other kind of questions and it\'s about the existence of god .how do we know that exists and it\'s here ?why he don\'t give us a real evidence of his existence ? like for exemple an apparition ?? please don\'t answer with typical answers like \"we are the proof of god\" or \"the creation of universe are the ultimate proof\" because in fact we don\'t know if we are made by Allah or Jesus or any other gods of any other religion so how can you be certain that : 1- there is a God 2- there is only one 3- he\'s the god of islam : allah thank you for paying attention to my questions