Need automatic ordering for bookmarks and links to them

Using Writer. My application is an email productivity tool that allows me an index into various message blocks that I copy and paste into emails. These are for a volunteer position I hold as the Treasurer of a non-profit.

There are many people that need some of the same information, but each email is custom fit for that person’s situation. So one member may need mid-level corporate membership payment info with link and benefits to becoming a member, while an individual will need the individual payment link, but same benefit information. So I have payment links under different indexes, and the benefit information under a separate
index. Now say they were set up as links 1,2 and 3. (I actually have over 40 blocks, each with own index and bookmark.) And I decide to now to include
an unlimited payment link, and need to place that after index 1 (mid-level corporate membership level
payment link). As it works now, I have to renumber the link names for the following links (2 and 3)
so I have room to put the new link in as #2, renumber the the links themselves, because
they are numbered in the bookmarks listing in the same order and numbering as the index and blocks are, then create the new link, create a new bookmark, and finally attach the new bookmark to that link. I would hope that when I create
a new index, the system could do the reordering for me.
I’m sure it’s a simple solution, but right now I’m confounded as to how hard I have made this, and could really use a direction steer as to if LibreOffice writer can do this easier, or if I should be using Calc, or if I should go to a different technology altogether.
Thanks!