monsters, animals, npcs, and lvling them up...

[zainale]

can someone link me to where I can read this information on d20pfsrd or Archives of Nethys?

[Dave Justus]

Is this what you mean? Monster Advancement

[zainale]

I think that may be exactly what I am looking for. if it also applies to animals. And I don't see anything that changes the "creature"'s saves scores based on their HD/LVL.

[Dave Justus]

It applies to any monster. Although by applies, that means it is a tool for GMs to use to adjust monsters, it isn't really a thing for players.

Scroll down to the Table: Statistics Summary in the Monster Creation Rules and it will show you the base values for good and bad saves based on HD.