Upload specific Photo photos to Google Drive I have a relatively large photo library (30 GB) stored in Photos.app, stored as one big 'Photo Library'. It is setup to sync to iCloud. I have taken some pictures on my iPhone, which is also synced to iCloud.

I want to upload a few specific photos into Google Drive. It seems there are a couple different ways I could do this. I could either access the actual photo file within the 'Photo Library' (perhaps by following this guide) and upload it directly. Alternatively, it seems that I can upload the entire photo library and then select specific images (as explained here) but that process was slow because my library is large.

What is the best way to upload a few of my specific photos stored in iCloud, accessible via Photo, to Google Drive?

An ideal solution for me would be to right click on the photo (or a group of photos) and 'share' to Drive, or something of the like.
Not having Goole Drive I am making an assumption here that you have a folder of some sort that you can drag files into and out of, similar to Dropbox.

If you select the photos in Photos.app that you want exported to Google Drive and then tap ShiftCommandE that will prompt you for the kind, size and quality of the picture. Once selected click Export and point the file dialog box to your Google drive folder.

Note that Photos.app will remember the kinds, size and quality settings from the last export so you will likely only have to select those options once.