You typically have to know the venue (or journal) you want to publish at. Then make sure to check their websites (regularly) for CFPs (call for paper). Then you

You typically have to know the venue (or journal) you want to publish at. Then make sure to check their websites (regularly) for CFPs (call for paper). Then you submit your paper by the given deadline following the given paper submission guidelines and wait until it is peer-reviewed. Then either it gets rejected or accepted (or some middle ground: asking for revisions).