Hey David,
first of all, thank you for the purchase!
Let me clarify if I got your question right: you’d like to create several categories and display links to category archives on the portfolio grid. If that is indeed the case, you can use the “link” project type to achieve this. This format supports thumbnails, so you can add images to the boxes; each can link to a specific category page (in the case of theme demo, e.g. https://satoristudio.net/ikebana/category/tutorials/). You can read more about the “link” project format on page 9 of the theme manual. Please let me know if this is going in the right direction!
Sincerely,
Andrii / Satori Studio