All you have to do is create a membership from the link I gave below.
https://www.coinbase.com/join/yksel_6
Verify your e-mail address after completing the necessary registration process. Then complete your profile information. After verifying the identity, solve the tests from the "learn and earn" section, and the rewards will come to your wallet. Do all the tests. Sometimes you can answer the wrong option. Try again until you find the correct answer and do the same for all the tests. Finally, convert the reward coins to xlm (stellar) by converting from the Coinbase wallet. From here, shoot to the Global stock market you want. That's it!!