To log in to the course you purchased from Writing.io, follow these steps:
Click this link to go to Teachable.
Click the "Course Log in" button.
Enter your email and password. Or, if you created an account through Google or Teachable, click the "Log in with Google" or "Log in with Teachable" button on this screen, respectively.
Click "Course Log in."
On your Dashboard, you will find each course you purchased through Writing.io.
Here's a quick video walk-through: