Hello,
a link directly to a bookmark is not possible, but you can create a link that jumps to the same place:
- Online: In https://tools.pdf24.org/en/annotate-pdf choose the Link tool and drag a rectangle over the area that should be clickable. In the small window that opens, choose Page and enter the target page number. Then save the PDF. This link jumps to the page, not to a position on the page.
If you want to open the PDF at a bookmark from outside, e.g. from a web page or another document: In https://tools.pdf24.org/en/bookmark-pdf you can give a bookmark a Named destination. Links with #nameddest= and this name, e.g. manual.pdf#nameddest=chapter-2, then open the PDF at this bookmark in PDF programs that support it.
Thank you for the suggestion of choosing a bookmark directly as link target, we will add it to our list.