QM365 has its own register of links. These can be connected to one or more processes and can be created directly from the link grid or from the individual process in PM.
This functionality is a separate list/register of all links with a title and a category. A link can be marked on multiple processes so that it appears every time you click on a box with that process. It is much easier to maintain such a list than to enter links in documents, PDs and Activities.
Also remember that a box in a process map can link to anywhere on the internet.
It is not recommended to include links in documentation such as documents, process descriptions and activities as it is very difficult to maintain. Rather, point to the link in the resource image and create the links there. It is much easier to maintain as a link can be used for many different processes.