If you go to Autodesk's website, and look at the system requirements (Tough, I know!) You'll see the answer to your first question.
Display Card Windows display adapter capable of 1360x768 with True Color capabilities and DirectX® 9 ¹. DirectX 11 compliant card recommended
If you continue to look on this same forum, you'll find the answer to your second question. Hint, look for my posts.
This message was posted on behalf of Intel Corporation
NUCs come with embedded graphics on the processor; it is not possible to add an external graphics card.
Now, our latest NUC 6i7KYK comes with Iris™ Pro Graphics 580. It already supports DirectX® 12, embedded DRAM 128MB, Max share Memory: 1GB and it exceeds True Color Autocad requirements.
More details are available in the link below:
Processor and graphics specifications:
Technical Product Specification 6i7KYK