To purchase coins you will need to select your wallet and open the coin shop. You can open your wallet by going to your profile and clicking on Coin button. In order to purchase coins, you will need to have an App Store or Google Play account. Coin pack purchases are not yet available on the Web version of Wattpad but once you have coins in your wallet, you will be able to unlock stories on the web.
You can also access the coin shop when you reach a paywall on a paid story. The coin shop will display all available coin packages and their prices. If you are a Wattpad Premium member you will get Bonus coins with every purchase you make. You can learn more about Wattpad Premium here.
If you are a Premium+ member make sure you use your unlocks before your subscription renews.
All Paid Stories have free preview chapters so you can decide if you want to spend coins on them. Please note that all Paid Stories are different lengths and some will require more coins to fully unlock. Below these options, you can see how many parts are remaining in the story.
You can read the stories you've unlocked as many times as you like. When you unlock stories with coins you are directly supporting writers, so they can keep writing stories you love.
Learn more about the Paid Stories program here: https://www.wattpad.com/user/PaidStories