You will need lights for more reflections, or better yet, add a sky with an HDRI image, add a compositing tag and uncheck “seen by camera.” As far texturing, add your base material first, then add your chrome texture after. click on your chrome texture and in type R1 (must be CAPS)in the selection area. Duplicate your chrome tex and change the selection to R2. This will make just your edges(or ROUNDS)chrome on both sides. All of this is dependent that you have a fillet cap on your extrusion.