I'm afraid I'm not completely clear on what you're looking to do and also don't know what software/version you're using. Are you possibly trying to create a multi-movie project/DVD in a Magix video program, so that you will have two movie entries in the DVD main menu, with each entry also having a sub menu with chapters? If so, start up the program and use the "New movie"/"Load movie..." options in the "File" menu to either create new movie or load movies from your hard drive (if you've already created them previously). When you have one movie open and you try to open the second one (either as new movie or by loading it from the disc), you will be prompted whether you want to close the first movie or edit a multi-movie project. You should pick that you don't want to close the first movie. This will switch the program to multi-movie mode. When opening/loading more movies to be added to the same project, you won't receive the same question again, as the program already is in multi-movie mode.
Now, when you switch over to the CD/DVD Editor, you will find that there's one entry in the main DVD menu for each movie, with possible entries for chapters in the sub menus.