Try the Commands Troubleshooting and Help page if you get stuff with server errors.
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Minecraft Give Player Head Generator
Mobs, Blocks and Other Heads: Some heads were added by Mojang, but not all mobs have been added and some players have names with non matching skins.
Enchantments: Heads can only receive Curse of Binding and Curse of Vanishing for enchantments.
Java Only: This feature is only on the Java Edition
Other give options: Many of the common give command data options are still included, some are not relevant to enchantment books, but many map makers have very interesting projects with specific requirements.
Minecraft Versions Permalinks
If you find yourself using a particular version all the time, you can link directly. There is some crossover between versions, so there will be quirks.