WordPress fetches this avatar automatically from your Gravatar.com profile, which is the default service for avatars in WordPress. This avatar will be shown inside your author widget, comments section… basically wherever your WordPress theme allows you to display it.
- Solution 1: Register at Gravatar.com with the same email you are using for the specific user on your website and that’s it.
- Solution 2: You can use some plugin which will allow you to upload your custom image instead of registering to gravatar.com. For example https://wordpress.org/plugins/wp-user-avatars/