Can you set cover image for the article

[jmooring]

Please look again, carefully, at the file structure in my previous response.

No:

content/
└── blog/
    └── article1/
        ├── article1.md 
        └── cover.jpg

Yes:

content/
└── blog/
    └── article1/
        ├── index.md 
        └── cover.jpg

See https://gohugo.io/content-management/page-bundles/