If you are asking vanilla enchants, just use an enchanting table with bookshelves on your island.
If you are asking about runes, use /warp infuser (infuser if you have any rank) to buy runes.
Drag and drop runes onto the tool you want it applied on. Be aware of the failing/destroying risk.
Combining enchants using an anvil is disabled. So you won't be able to combine 2 Protection I books into a Protection II book.
Hope this answered your question, if not feel free to reply.
Greetings,
Yoyo