The skinpack installation is different depending on which version you're generating for.
1.21.2 and later:
For this version you install it like you would many of our other packs, the skinpack is a datapack and a resourcepack so you place it in both folders, activate it and you're good to go!
1.21.1 and earlier:
For this version you install it like you would a resourcepack, so you place it in your resourcepacks folder, activate it and you're good to go!
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