All ConvertKit plugin tutorials:
1. Get your convertkit API Secret this way (Please Note: API Secret is different from API Key.)
2. Then go to your stealthseminar account, and go to marketing plugins by clicking on your gravatar
3. Go to ConvertKit on the same page and click on connect. Then add your own API Secret in the corresponding input field and hit connect.
4. Now you can go back to your event and click on plugins. You will now see ConvertKit there.