does any of you know any other book websites that gives free ebooks
You have to be careful because there a lot of illegal sites out there that don’t have permission to distribute fee books. Check out OBOOKO, they have been online for seven years and are 100% legal. They have a great range of fiction and non-fiction ebooks to download free. They are a bit thin on programming and IT books at the moment but are well worth taking a look: http://www.obooko.com/obooko_compinternet/free_ebooks_computers_internet_001.html
Possibly the two best books available on programming (The Structure and Interpretation of Computer Programs and How to Design Programs) are free online.
And [I am not necessarily saying you should take advantage of this fact] most older (and some newer) textbooks are saved on public facing parts of university/college sites, or on github (often where a person is working through code exercises from a book). Just Google for the PDF. This won’t generally work with language/framework du jour books, but does work with canonical textbooks (eg there are hundreds of copies of the Dragon book floating around) if you need a bit of a deeper understanding of why and how things actually work.
There are some free books here: https://topcsbooks.com, even though most are links to Amazon. For example “A Graduate Course in Applied Cryptography” at https://topcsbooks.com/course/introduction-to-cryptography/university/stanford-university/ is free.