How does Amazon prime work ?

[Imfat]

How much per month.
Can I join then cancel before I start paying. Does it include books on kindle.
Thanks

Another question. Can I download lots of the books on prime then cancel my subscription.

No. You will only have access to books while you pay the kindle unlimited subscrption. It is a seperate subscription to amazon prime.

Amazon prime includes free books but I don't know if they would disappear from your kindle if you cancel

Ones you pay for wouldnt go though I'd assume

it's £7.99 a month, that also include prime video,

Most UK libraries offer free ebooks. Not compatible with kindle, though. (unless you have the kind of kindle that is basically an android tablet)
Kobo readers can access some free books from their own site plus ebooks from the library using 'libby'.
If your library uses 'Borrowbox' or something else, you can still read them on the Kobo, but they need to be borrowed on a laptop/PC and transferred via a cable.

Prime is often offered on a 3 months free deal or similar, look out for that, use and see if it meets your needs and cancel at the end of the trail if it does not. The free books go from your account when you cancel.
If you subscribe then cancel you will still have to pay the months subscription unless you have not used it.

It's £8.99 now unfortunately!