In order to create bibliographies using the McGill Guide (9th edition) citation style, you need to first add the McGill Guide citation style in the Zotero settings by selecting Edit > Settings as shown below:
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Select Cite, then "Get additional styles":
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Search for "mcgill guide" in the Zotero Style Repository, then select "Canadian Guide to Uniform Legal Citation 9th Edition (McGill Guide)" from the list of search results:
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