Here are three public ebook resources that allow people to access ebooks for free.
Internet Archive and Libby require people to create accounts and then lets them check out ebooks, similar to physical libraries. In order to check out books from Libby, you must have a library card, as it is linked directly to libraries' catalogs, allowing participating libraries to continue to check out materials during the pandemic.
Project Gutenberg focuses on books that have expired copyrights, so there are virtually no restrictions on reading, downloading, and printing.