Update with Child Theme

Hi,

I just want to update enfold to the newest version, but have already some changes and customizations in my theme.

So, what is the easiest way to update the theme without getting the customizations lost? What are the steps to use a child theme for this?
When I use a child theme, will I be able to update the parent theme in future without loosing my customizations on the child theme but still be able to take advantage of the benefits of the newer theme? Or will I have to update the child theme every time when a new update appears?

Thanks a lot for your support!

Best Regards!