InDesign book questions

There are great tutorials on Adobe, and the one for footnotes in InDesign is here: https://helpx.adobe.com/indesign/using/footnotes.html

1. How can I make sure that all files added to the book follow the same footnotes settings regarding space from text, divider etc 

2. Also I want to force that at the beginning of each chapter the numbering of the footnotes  restarts to 1.

Footnotes are a document-level feature, so one way would be to set up a single InDesign file with your preferred footnote settings, save that as a template file (INDT), and then base each chapter off of that template file. That works great when you have zero chapter files and are going to set about creating them. But if you already have seventy chapters all laid out, then it's comparatively laborious to go through each file and fix the footnote settings by hand. 

But adjusting document footnote options with a script is comparatively easy. 

var doc = app.activeDocument;
var footnoteOptions = doc.footnoteOptions;
footnoteOptions.startAt = 1;
footnoteOptions.ruleOn = true;

That script silently changes the footnote options in the active document to start at 1 and turns on the divider. The full range of options available is here: https://www.indesignjs.de/extendscriptAPI/indesign-latest/#FootnoteOption.html 

Work wisth styles. In the book panel menu you can synchronize these styles and master to have them equal in all chapters. After changing these styles in the source document run the synchronization.