To send a sample project you can simply take the project you’re working with and remove everything from the project folder except fro Config, Content, Source folders and the .sln and .uproject files. Then zip the folder and add as an attachment to your post.
To get the DXDiag you can type DXDiag into the Windows Explorer search bar and run the .exe if you click the Save All Information button it will produce a .txt file that you can add as an attachment