Step 1: Click on this page https://www.reddit.com/prefs/apps and log in with your Reddit account.
Click "Are you a developer? Create an app..." button.
Step 2: Enter App name, description. About URL should be your website URL.
Step 3: Navigate to "apps" tab > Click "edit" to get more detail info of your app
Step 4: Copy web app (App ID) and secret (App secret) to Social Login Pro app configuration page.