Hi Simon,
sure, that is possible using Stardog. I think the easiest way to get started is getting a Stardog Cloud account, where you can setup a free server instance (see details).With Stardog Cloud you can use Stardog Studio to add data (e.g., uploading RDF files) and query your knowledge graph (using SPARQL). You can visualize and explore the graph using Explorer.
There are also different tutorials for getting started in the Knowledge Kits section and you can find more materials in the official documentation (e.g., in the Tutorials section).
I hope this will help you getting started with your project.
Best regards
Lars