Group J Exoplanets And Aliens

there is a big mystery whether aliens exist or not but there has been sciencetific evedence that there is bacteria on other planets wich is counted as life on another planet. if there is a planet that is almost the same as earth (it has earths resorces. e.g. water, land, some sort of vegetation and oxegen.) then there is going to have most likely living thing on it, if not now then maybe later in the future. also if you think about it there are so many planets out in space, how can we be the only living life form in the whole of the universe?