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As you note in a comment, the guide to formatting is on the Main Meta
Like any text editor, you can put in line breaks and tabs once you know the tricks.
Some sites have additional formatting features, specific ...
There are problems with the text-editor for writing questions
The text editor uses Markdown. You are limited to what it will let you do, but it is quite a good trade off between power and simplicity. There's no way I know of to do indents, but you can do block quotes, indent lists and code blocks. For example, the block quote at the top of my answer is done ...