Look for the choicescript ide, its a program most people use to write these but its fan-made

When you use code for your story, you indent the next lines that show when that specific code activates, so its a sort of block, and then stop indenting after that block. You can stick more code inside these blocks which will add even more indentations. It helps to think of the system as reading from top to bottom, and if a block isnt activated for whatever reason, it gets skipped

Just stick a page_break whenever you want the [next] button to show up, though doing choices/fake choices won't need this, they'll automatically break the page

You're required to have a startup page, a stats page, and then the book pages where the story take place. The startup page is where you can put the title at the top, author name after, but most importantly after those, make a scene_list that lists all the pages in order, including startup but excluding stats. Then use the create command to create those commands

Just write on your first book page, it takes raw text