To use the Axotic theme you must need to create a content key from your admin panel. Generate a new Content API Key by using the following steps :
1. From Ghost Admin Dashboard click on Integrations
2. And then click add custom integration
3. Write any name for that custom integration and then click Create
4. Now the key will be generate, just hover over it and copy the code.
Congrats! You got your ghost content api key for your blog. Now use that in next step.