Q: Can I share a folder from iCloud Drive?

No - iCloud drive and its folder structure is strictly for sharing with one account.

For some iWork documents and photos, you can share them individually or by adding someone to a shared photo album, but that's based on the app design and not a more general folder based file sharing idiom.

You could use Apple's MailDrop feature to email each file to the recipient(s) that need to share the file, but it wouldn't be anything that's hosted and really shared in the sense that a change to the file by one user would then be reflected on the cloud.

Use Dropbox.

Hi Eric, what do you, yourself, use?

I don't share files with others very often, but when I do I use Dropbox because I use it for syncing some items. I use it so little I can keep the free account.