Hey welcome :)
There are a lot of different maps. Paizo makes a variety of maps for different types of terrain, which you can find for example here and here. These maps are wet and dry erase, so you can draw on them to indicate where something is happening or what part of the building is on fire, and erase it again afterwards. They're very reusable.
The Starfinder maps product line does most of the space station sort of maps, while Pathfinder makes more conventional wilderness terrain. Starfinder adventures use maps from both product lines.
Not all maps in scenarios/modules can be found in the store; some are custom maps only used in that particular adventure. These you can draw yourself, on a basic terrain flipmat or on flipover paper. Typical sheets of flipover paper are a bit bigger than a standard flipmat. Custom maps in scenarios are often the same size as a flipmat, so that works out quite well. When buying flipover paper, look for one that has an 1 inch grid. A roll of 50 sheets lasts for quite a while and costs about 10€ where I live. (Pawns are usually 1 inch base.)
You can also print the maps of course. You can usually select the image by right-clicking on it in the PDF, then copy-paste to your favorite image editor. You can play with color, brightness and scale a bit and resize it to 1 square = 1x1 inch. GIMP is a suitable free program for it. I especially like these functions in it:
* Filters > Enhance > Unsharpen Mask. Actually sharpens the picture, useful when magnifying.
* Filters > Artistic > Oilify makes things a bit fuzzier, good to make things less obviously pixelated if you just did a lot of magnification.
* Colors > Levels gives you some sliders to elegantly brighten very dark maps.
* Image > Guides allows you to put in guidelines, which you can then use with Image > Transform > Guillotine to slice up the picture. That way, you can divide it into smaller pages that you can print with a normal printer and then tape together.