Either modify the game's resource files or use the scripting function OverrideObjectTooltipNameAndDescription().
Added 4 minutes later
Another question :) Let's say I want to create a quest to kill wolves. But they will be scattered across the map. Let's say 5 wolves, in groups. The same applies to cities, for example. I don't know if you understand me :o :D
Added 5 hours later
How do I change the map's lighting? Specifically, through scripts.