It's actually quite simple. As long as you are a registered user (not an ordinary registered user, but a paying user), you can download most books (and some books, mainly new books, even registered users are powerless. You can only get them by file transfer).

However, the cost of directly paying for registration and downloading is very high. If necessary, you can go to Taobao-Baodou-Buyou-Xiu Xiu's data service, and the monthly fee is about 2-5.

If you want to download without spending money, you have to wait for netizens to publish accounts (generally, these accounts are about to expire, so use them quickly)