To get the Publishable Key and the Secret Key from Stripe, you need an account at Stripe (www.stripe.com).
1. Open the following website www.stripe.com and click on "Sign in".
2. Now that you have logged in to Stripe, the dashboard opens. In the left menu, first click on "Developers" and then on "API keys".
3. Your account will have two sets of API keys – Live and Test. To access both, use the toggle switch in the left menu. Select “View Test Data”. Test keys will have ‘a _test_ text’ in the name.
To switch Stripe to the Sandbox (Test Payments) mode or Live (Real Payments) mode, click on "View test data" in the left menu. Note that Sandbox and Live Mode have different keys.