? Which Kindle Will Handle My Needs And How Do I Do My Crossword Puzzles On Tha

Hi,  I am interested in buying a Kindle for a family member who loves to play crossword puzzles as well as read books.  Does the Kindle allow one to buy / download Crossword Puzzles and then how would one easily fill in the puzzle ?  One store clerk told us get the one with the keyboard pad at the bottom and then use the keyboard buttons, another said NO, get the virtual keyboard and touch the virtual keyboard ?  Another sales rep told us to buy the simplest version, while another told us we need the Kindle Fire to download crossword puzzles and the books he wants.  We are all confused about which one to buy and if we really need the 4G system or if we can just plug it into our desktop computer and download books / crossword puzzles / borrow books from the library.... right from our desktop and transfer it to the simpler Kindle ?  We need advice to buy the easiest Kindle to use for a Crossword and Book enthusiast.   I thank you,  Steve