Launch Greyscalegorilla Studio and download any HDRI texture, right-click the downloaded HDRI thumbnail and select "Show in File Browser", start 3ds Max and drag the ".hdr" file into the Material Editor window.
2. Click Lights on the Create Panel and choose Arnold from drop-down menu then add Arnold Light.
3. Select the "Arnold Light" object and choose "Skydome" as shape type. Then on the Color/Intensity section select Texture and drag the output connector of the HDRI texture node to the texture box.
4. After you assign the texture your HDRI reflection will be updated. You can enable Light Shape visibility from Shape Rendering section to make it visible as background on renders.
5. Go to Arnold menu and select Arnold RenderView and render your scene.
