If you encounter the 'Missing Library' issue while trying to import Excel, this is due to Excel not being installed on the PC.
To avoid Excel version conflicts, where a built-in version would conflict with the version the user is using, the user should install their own version.
However, due to the rise of the subscription versions of Office, you may need to install the libraries, as the Web version does not install libraries on the PC.
Note that some Office subscriptions offer offline installations or desktop versions (their naming varies), in which case you should install that.
Below is the link from Microsoft's website to download the libraries.
If Microsoft's links become inaccessible, I've put the files on our storage servers.