https://www.guyrutenberg.com/2014/05/02/make-offline-mirror-of-a-site-using-wget/

Sometimes you want to create an offline copy of a site that you can take and view even without internet access. Using wget you can make such copy easily:

wget --mirror --convert-links --adjust-extension --page-requisites --no-parent http://example.org

Explanation of the various flags:

    --mirror – Makes (among other things) the download recursive.
    --convert-links – convert all the links (also to stuff like CSS stylesheets) to relative, so it will be suitable for offline viewing.
    --adjust-extension – Adds suitable extensions to filenames (html or css) depending on their content-type.
    --page-requisites – Download things like CSS style-sheets and images required to properly display the page offline.
    --no-parent – When recursing do not ascend to the parent directory. It useful for restricting the download to only a portion of the site.

Alternatively, the command above may be shortened:

wget -mkEpnp http://example.org

Note: that the last p is part of np (--no-parent) and hence you see p twice in the flags.