I recommend an internet search on the term "physical geography".

The most realistic and accurate fictional maps are the alternate timeline Earth maps. They tend to be very plausible in terms of physical features. The best fictional maps are, in my opinion, the ones that best support their story. They may have physically implausible features like a mountain spire hundreds of miles high or oceans that fall off the edge of the world, but as long as they support the story and are self-consistent I find them very good.

The essence of mapmaking is to maximize what's important to the purpose of the map while minimizing what's not important. If your map is about physical accuracy then the capital city won't be more important than a small village. If it's a typical cultural map, then govenmental subunits, navigational aids such as roads, and barriers to trade such as mountain ranges will feature prominently. Finding the perfect balance is tough.