One of the difficulties people have when they start with Scrivener is that they treat it as a standard basic word processor, like Word. It isn’t: it’s a lot more powerful than that, but that means it does some things slightly differently.
I’ll give you the steps for your immediate problem later on (it’s a very simple solution), but I want to explain the background first, because it sounds like at the moment you’re not aware of the differences, and that’s naturally causing some frustration.
In Word, the way your manuscript looks on the screen is exactly how it will appear on the page. So, you format it to submit to a publisher and all is good. Until, that is, you find you need to reformat the same Word document for an ebook, or for a self-publishing house, or any other type of output.
Scrivener isn’t WYSIWYG like that. In Scrivener, it doesn’t matter what your text looks like on the screen — it can be in 18pt green Comic Sans if that makes you comfortable — because you will choose the output format when you compile the document at the end. That is, when the project is ready, you choose to output it as a standard submission manuscript, or as an ebook or several other formats just by clicking a couple of buttons.
You don’t have to change the project at all: instead the compiler ‘knows’ what a standard manuscript submission looks like and automatically changes your 18pt Comic Sans to 12pt Time Roman double spaced with first line indents.
Choose an ebook target and the compiler changes the same project to a suitable format, again, without you having to do anything at all to the words in your project.
So, it really doesn’t matter what the words look like on the screen in Scrivener: you worry about that when the project is finished and you’re ready to chose what the final product will look like.
Now, if you like writing in Times New Roman 12 pt with a first line indent, that’s fine, you can do that too, as long as you understand that this is a separate process to producing the final document.
Changing the on-screen text format
The basic steps are:
Open the settings panel (Preferences on the Mac, File > Options on Windows) and go to the Editing > Formatting tab. You’ll see something like this:
Use the formatting toolbar to change the dummy text to look the way you want it to (font, line spacing, indents and all). Now every new document you create in this or any other project will use this as the basic paragraph format until you change it.
NB: that won’t change documents or projects you’ve already created, it’s purely for new documents.
So, you have to select the documents you’ve already created in the Binder and choose Documents > Convert > to default text formatting. As the name suggests, this will update their formatting to your new defaults.
Finally, I really would encourage you to do the Interactive Tutorial for V3 on the Help menu ASAP. It will only take an hour or so to skim through and it will save you a lot of time and frustration afterwards.
Scrivener has a few basic concepts (including the ones I’ve just explained) and the tutorial walks you through them — if you try to work on the assumption that it’s just another Word Processor like Word, then you’ll make thing hugely more frustrating for yourself and you won’t get the best out of the program.