Hi,
1) What your are looking for is called a backlink.
2) In DokuWiki there is a backlink button. With current default template, hit the chain icon on the right of the page and you are presented the list of all pages that link back to the current page.
There are (at least) two plugins that can embed the list of all backlinks in a page :
backlinks and
backlinks2. Don't know if they are compatible with current DW version. Don't know how they work, so it is probably a good idea to use
~~NOCACHE~~ in the same page.
/Schplurtz