Start from a new file in Blender. Depending on your start-up file you might already have a light in your scene. Press F12 to render. If you get an error about no lights in the scene then simply add an area light (Shift A->Lamp->Area) and press F12. (image of first render)
Lighting a scene is usually done by area lights or a HDRI. Go to the World panel and enable the HDRI option and open a HDRI file. Render.
If your start-up file in Blender has the sun lamp, you might not see the HDRI light up your scene now because the sun lamp is very bright and overpowers the HDRI. Stop the render (ESC) and enable viewport rendering (Shift Z). Select the sun lamp and decrease its Gain. You probably need to use a low gain(0.00001) as the sun lamp is very bright.
Add a Glossy material node (Shift A->Material->Glossy) and connect the material socket to the material socket on the output node. Open a texture in the image editor or drag and drop it into the editor. In the node editor add a texture node (Shift A->Texture->Image) and select the texture in the node. Connect the color socket from the texture node to the diffuse socket on the material node. If you have a roughness/specularity texture and a normal map texture you can add those too in a similar way. Drop the two textures into the image editor and duplicate the texture node (Shift D) two times. Select the roughness/specularity texture in the first node and connect its color socket to the roughness socket on the Glossy node. Select the normal map in the second node, enable the normal map option and connect the node to the bump socket on the Glossy node. Render.