which software to use to make the rules's game?
As a fellow aspiring Game Designer, I stick with word or excel for initial content.  Use anything you are familiar with, as content is the only thing you should be worried about.  Unless you plan to self publish, publishers are going to scrap your design for something that they'll get professionally made.  If you do self publish, then I recommend sending it to a professional designer with experience in tabletop games.  Also, you can post to sites like Board Game Designer Forum for peer review by published game designers.  (https://www.bgdf.com/)  There are a ton of articles and advice out there on layout, content and form.  Here are a few:

https://boardgamegeek.com/thread/405444/rule-book-writing

https://www.boardgamegeek.com/article/3277179

http://www.leagueofgamemakers.com/?s=write+rules

Best of luck on your game design!