Non-Fiction – investing, finance, etc. – UK based

I am interested in learning more about how money works in the UK – stocks, investments, accounts (e.g. ISAs, etc.). I have almost 0 knowledge / understanding of the subject but would like to learn quickly. Please would the lovely folks in this sub be able to suggest a non-fiction book that starts at the very beginning (assumes the reader knows nothing) and is reasonably easy to understand? Thanks!