It was written by royal pundits Omid Scobie and Carolyn Durand and aims to provide an in-depth look at Sussex life.
Tensions between Harry and his brother Prince William are also covered in the book, which could create further tensions in the royal family.
These tensions reached their boiling point when William warned Harry not to rush with Meghan, according to the book.
The book will be released on August 11.
Sources have suggested that Meghan and Harry will not focus on releasing the controversial book, but instead celebrate Meghan’s birthday.
READ MORE:Meghan and Harry’s royal outing “changed Charles and William’s relationship”
“It’s something that has been a tradition of her even before she was famous. This is something she learned from her mother.
The book also explores Harry and Meghan’s personal relationships and in particular what led them to step down from their royal duties.
However, the Duke and Duchess say they haven’t given their opinion on the book or offered any interviews.
Inside the book, there are intimate details of the relationship between the Duke and Duchess in her early days.
In particular, the book explores how quickly their relationship has evolved.
The book said one of Meghan’s friends said: “Three months after starting their relationship, they had already started exchanging the words ‘I love you’.”
An excerpt obtained by Entertainment Tonight reads: “Harry said it first, but Meghan immediately responded, ‘I love you too.’ “
“From there, it didn’t take long for them to start talking in non-oblique terms about their future.”
“While Harry and Meghan kept a low profile, the prince’s presence could not go unnoticed in his neighborhood.
“It didn’t take long for Harry’s visits to become an open secret among the residents.