1. You can't as far as I know.
2. Use a paragraph style on the text and in the Inspector palette > doc tab > TOC > check the style so it appears in the TOC. You can read more about it if you download the Pages User Guide from your Pages Help menu.
3. When using a word processing document you don't have to use the Section route. You can select the text you want to move and then drag it to another location in your document, or use Copy and Paste to move it.
For creating the TOC you only need to click somewhere in the beginning of the document where you want the TOC and then go Insert > Table of Contents. The text behind will move. no need to add a page first.
4. For this you add the section break and in the inspector palette > Layout tab > sections > First page is different