Can I put a roof rack on my Tesla?

Yes. There are several options to choose from. The Tesla Roof Rack is probably the best in terms of appearance, wind noise, and range impact. Yakima offers a roof rack solution, but the wind noise at highway speeds is comparable to banshees singing at a campfire.

There are suction-cup mounted racks that people have said good things about, although they do have the disadvantage of putting pressure directly on the glass roof and the risk of really bad things happening if the suction fails while driving.

Note that putting something on the rack (bikes, skis, kayaks) will have a significant impact on wind noise and probably range loss.