Rpg Maker Developers Group

This is the pack i bought: https://limezu.itch.io/modernexteriors

i copied the "Modern_Exteriors_Complete_Tileset_48x48.png" and pasted it inside my RPG MZ tilesets folder to use it, inside the program i went to Database -> Tilesets and created a new one containing the png in one of the 9 empty slots, but when i tried to use the tilesets i noticed that the map editor only lets me use a tiny part of the png (only lets me use what is in the image im showing).

Im a complete novice at using RPG so i don´t get if this happens because the program only accepts a certain ammount of tilesets, after all the Modern exteriors png contains all the tilesets (that are a lot) in just 1 png, and if i want to add the tilesets separately i find that all the tilesets (5.660 elements ) are separated 1 by 1 by searching the tileset folder"singles" but RPG MZ tileset database only accepts 9. i searched around and didn´t find any "Modern_Exteriors_A1", "A2" and the like to insert each to their corresponding slots.

I also tried downloading the Modern Exteriors RPG MV but its tilesets are also separated in a total of 120 groups, im lost.