There is no need to bother about the URL. You can make any page show as the home page. See Settings > Reading for choosing which page to use. That option is actually for you to choose which URL to forfeit, and show that content as the Site URL.
So, create a draft and make it how you like. When you are ready, publish it. Go to Settings > Reading and select that page as home page. You can delete the old one.
Or you could refrain from publishing the new one and simply copy it all into the existing page. (depends if you have anything special for CSS or a plugin using that page ID for something…)
I got it. Thank you for your answer.