As you're not able to see the export option in Lightroom, could you please let us know the exact version of Lightroom you're using?
Also, I would suggest you to go to the Preferences of Lightroom. And then the Interface Tab, in there please change the Font Size to Small. Restart Lightroom , and then see if it helps. If the above steps does not work, try to lower the screen resolution of your Laptop and then check in Lightroom for the Export option.