How to Sell Dissertation and a Book ?

When it comes to selling your own book on the web, people choose to self publish via platforms such as amazon. However, I was thinking of
creating my own website and selling it there. Perhaps as an ebook or a print version. My idea is to write post some unique content over for three weeks
and then offer my book, while optimising the website for SEO.

But I'm a newbie and not sure how to proceed. What do You think?

It would be much easier to publish via Amazon. You would still be able to create a website and promote your book separately, but Amazon can turn it into a print copy too. If you were to go fully self published, you would have the hassle of having to find printers and ordering a minimum volume of copies which you might not sell.

And, of course, Amazon already has huge number of people searching for both ebooks and print, so you have a market just waiting to bring you sales.

That is what I'd do, publish on Amazon and still promote using my own site.

Or should I put the content of the book into the website and let people read it from there by paying a subscription or so? The reason for that is I'd like to keep the book as cheap as possible, like around 1 or 2 pounds, on amazon it may be more expensive and I would give so many fees to them.

Well, I've never looked in any great depth into Amazon publishing, but I believe that it is free for ebooks (not sure about print, the page is unclear), and that you can set your own price and receive 70% royalties. That's all I know about it, I'm afraid...Perhaps someone who has tried it can respond.

I don't think that a subscription system would work very well unless you were a really well known author. Creating the ebook and selling it yourself would be better than that. Another consideration, if it is possible to do with your manuscript, could be to split it up and turn it into an adsense site, and monetize it that way. I'm not sure how workable that is though.