GNU/Linux: $HOME/.minetest/games, where “$HOME” refers to your home directory.
Mac OS: $HOME/.minetest/games, where “$HOME” refers to your home directory.
Windows: into the games directory found in the main program folder in which you have installed Minetest. It is the directory containing the directories like bin (which in turn contains minetest.exe), builtin, client, doc, fonts, games, locale, mods, textures, etc.
HOWWW???
Put the cavegame folder from the zip in your minetest/games folder.
Or download from the in-game content browser.
https://content.minetest.net/help/installing/
That link can be found directly under the download button, it will tell you more about installing games/mods/texturepacks/etc.
how to find minetest/games folder
That depends what OS your running and potentially where/how you installed minetest. https://wiki.minetest.net/Games
GNU/Linux: $HOME/.minetest/games, where “$HOME” refers to your home directory. Mac OS: $HOME/.minetest/games, where “$HOME” refers to your home directory. Windows: into the games directory found in the main program folder in which you have installed Minetest. It is the directory containing the directories like bin (which in turn contains minetest.exe), builtin, client, doc, fonts, games, locale, mods, textures, etc.
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