Minecraft expects certain parts of your project to be in certain locations, such as textures and JSONs.
All locations and items covered in this page are relative to your
mcmod.info file is in the root directory.
Blockstate definition files are in the JSON format and are in the
Localizations are plain-text files with the file extension
.lang and the name being their language code such as
pack_format of 3 is specified in a
pack.mcmeta file, the language code should be lowercase.
They are located in the
Model files are in JSON format and are located in
./assets/<modid>/models/item/ depending on whether they are for a block or an item, respectively.
Textures are in the PNG format and are located in
./assets/<modid>/textures/items/ depending on whether they are for a block or an item, respectively.