I can confirm that Kindle does allow book lending, but with some limitations. Kindle's lending feature lets you loan eligible books to another person for 14 days. During this period, you won't have access to the book yourself, which prevents simultaneous reading. The process is straightforward: you go to your 'Manage Your Content and Devices' page on Amazon, select the book, and choose the 'Loan this title' option. Not all books are lendable, though. Publishers decide whether to enable this feature, so many newer or popular titles might not be available for lending. I've found that classics and older bestsellers are more likely to be shareable.
One workaround I've seen people use is sharing an entire Amazon Household account, which allows two adults to share Kindle libraries. This method has its own pros and cons, though. While it gives access to all purchased books, it also means sharing payment methods and personal data. Some readers prefer using services like BookFunnel or author-approved sharing platforms, especially for indie books. The digital rights management on Kindle can feel restrictive compared to physical book sharing traditions, but understanding these systems helps maximize what's possible. I often remind fellow readers to check the book's details page before purchasing if lending is important to them, as Amazon clearly states whether a title is lendable.