The Resource pack is available publickly in the websites below and only these are official, this repository is for managing and incase anyone wishes to test features. If you wish to give it a test run feel free to download it and give your feedback!
https://www.planetminecraft.com/texture-pack/shrimp-s-immersive-interfaces/ (links to the other 2) https://www.curseforge.com/minecraft/texture-packs/shrimps-immersive-interfaces https://modrinth.com/resourcepack/shrimps-immersive-interfaces
Warning
To use the pack it must be extracted from the downloaded file the final folder structure should be resourcepacks \ Immersive-Interfaces \ assets + pack.mcmeta
Note
The required fonts are set in the English (United States) language, if you wish to use your own language you can execute the script created by @Wolphwood in assets/minecraft/lang/$_langs.bat