Self publishing self help?

Is anyone proficient in... well, Im not sure which program yet, but basically formatting and compiling books?

I am working on putting together a module for roll play, and trying to populate all the monster pages and NPCs, magic spells, etc etc etc... I am trying to streamline things so keep them both more uniform and easier to enter.

Ive looked up a few ways to do things, and the closest thing I can find requires I write a visual basic program to generate the content or use a markup language (old school HTML being the only one I had any experience with)

The approach I was trying to take was supposed to go something like this:

Enter the data in a spreadsheet, such as:
Page, Name, Class, Level, Inventory (Im just making things up for example)
3, Bob, Bard, 3, Bullhorn
4, Jill, Wizard, 4, Wand
5, Kris, Rogue, 2, Lockpick

And have some program (such as power point or publisher) that can do formatting generate a page per character, with the name as a field at the top in one font, the various stats in blocks (above is oversimplified, the text fields might have background stories, key traits, images or links to images and so on) would then autopopulate a template one page to a line in the spreadsheet. In this way I can add dozens of monsters, NPCs, and whatnot without forgetting some field or spending weeks on formatting only to have it need to be redone every time a field changes or is added or removed.

I have found tutorials on how to link the fields between powerpoint and excel, (and their openoffice equivilant I use), so any info put in the spreadsheet shows up formatted on the presentation page, like I want, but I can only do it one page at a time- it doesnt increment a row on the spreadsheet for each new page (just is the same as the page that was copied). I could write a formula that involves cells by row in the spreadsheet program but cant figure out how in the powerpoint analog.

Anyway, I figure theres a "proper" way that books are formatted that maybe someone here is famikiar with? As an example, the "monster manual" for DnD is kind of what Im going for (but a different system, images, everything.. just using that as an example of uniformity) (said manual can be viewed on archive.org)

I habe like 4 different projects with hundreds of pages each to put together, so Id be thankful for any ideas.

If anyone else knows anything about this subject, I'd like to read about it.

I worked at a shop that printed and bound books in 1987. I'm sure things have changed