How to add multiple page .pdf file (book)

How to add multiple page .pdf file (book) to my web site?

Do you want the book to be downloadable? Do you want to charge money for it?

Or are you thinking of embedding the book in the page so that it can be paged through?

I want to attach exhibition catalogues for free.
It would be nice to be able to flip through the pages.
I was thinking at first it would be a download that opens up in the browser window.  
Not sure how to upload a .pdf file? Is there a  ftp site?

OK, so its pretty easy. 

What you can do is create a page and add copy and images to it to describe the brochure.  Maybe add a download button if you want. 

Then all you need to do is add a link to one / more of the copy, image and button. 

For the first link you add you will be given the option to create a link to a file. Use this to upload your pdf. 

For the other links to the same brochure you use the 'link to file' but rather than uploading you point to the file you aready uploaded. 

On desktop the file should open in the browser where the user can read it and/or download it. On mobile it usually downloads to local storage. 
 

See here for more information - https://support.squarespace.com/hc/en-us/articles/205813928-Uploading-and-managing-files

WOW! SUPER! THAT IS EASY! I AM NEW HERE... just started to build my site:)

...is something like this possible? embedded catalogue just to flip through?  https://timmmagazyn.pl/wroclaw/archiwum-numerow/timm-magazyn-numer-3

Those flip things can be embedded but with varying degrees of difficulty. 

On one system I've embedded all I needed to do was force the aspect ratio of the iframe holding the pages so that it worked correctly on desktop on mobile. That was a hosted service.  This is pretty easy stuff. 

There are other solutions where the scripts need to be installed on the Squarespace site. That is more challenging because they usually have a folder structure that (without going into developer mode) would need to be rewritten to cope with Squarespace's single level /s/ directory structure.  This is can be painful (and sometimes impossible) to implement without racking up time and money. 

If you're going to do it I suggest you post a few possible solutions up here to get guidance from myself and others as to which would be easiest to implement.