On your Kindle Home screen, find the book
Press and hold the book cover or title
Tap Remove from Device or Delete from Device
Confirm if prompted
To delete multiple books, go to Library
Tap the filter or sort option if needed
Select the books you want to remove
Tap the menu or more options icon
Choose Remove from Device or Delete from Device
Confirm if prompted
To delete books from your Amazon account, go to Manage Your Content and Devices on Amazon
Sign in to your Amazon account
Select the books you want to delete
Click Delete
Confirm the deletion
On Kindle apps, open the library
Press and hold the book
Tap Remove Download or Delete from Device
Sync your Kindle if the book still appears