Here are the top 9 alternatives of z library that you can use to download the ebook.
1. Gutenberg
2. Overdrive
3. Freebookspot
4. epdf
5. ebook3000
6. Bluesyemre
7. AvaxHome
8. Literature Network!
9. The Open Library
For more read - https://onlinegeeks.net/z-library/