Word and Writer are based on different principles. If you’re migrating, you are advised to read the Writer Guide for an introduction to these principles, notably styles which are much more developed and consistent in Writer.
You’ll need to make adjustments to your existing .doc(x) files. In order not to lose these adjustments, save in native .odt format, otherwise your documents will incur conversions when loading and again when saving resulting in important loss of formatting (due to approximate equivalences) and progressive damage (due to cumulative effects).
Regarding your question proper, sections in Writer are part(s) of a page where the “geometry” is temporarily different from the containing page, mainly number of columns, without affecting intrinsic attributes like page number, header and footer.
What you need is to play with page styles which assign attributes to a contiguous set of pages bounded be a special page break (Insert>More Breaks>Manual Break, not the usual page break which does not give access to all options). Depending on what you require from other attributes, you may need to create a new page style (a simple page number reset without changing other attributes – margins, header, footer, … – can be done on the current page style). You tell which page style is activated after the break, eventually the same but it must be explicitly designated, and you give the starting page number.
Note that converting documents from Word will result in a real style mess hampering your formatting performance because Word relies mainly on manual formatting. Writer must conservatively guess author intent and this gives rises to many many single-use styles. This is noticeable in character and page styles. If your documents are maintained on the long term, you’ll be better off to paste their contents in a blank Writer document and restyle them completely after having defined your graphical charter (=set of styles) in a template. Template are special Writer files hosting your styles and initial text for reuse over a collection of documents, allowing consistent look and automatic update when the charter changes.
