Save the generated file in the same folder as your LaTeX document.
If you are using Overleaf, click on the Upload button, then select the .bib file to add. You can rename it at any point, but ensure that the file is saved with extension .bib.
The unique keys generated by EndNote are not user-friendly when compared to those generated by Zotero or RefWorks. You may want to update each key with memorable information to make those searchable e.g. author / date / title.
library@imperial.ac.uk
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