How do I paint this wooden desk a metallic rose gold?

Hi ! Try getting a product by Krud Kutter , called a de glosser ! Clean the desk with that ! That will not only clean the piece , but take off some of the glossy finish , to allow the paint to adhere to it better . Try that first , then test a small section ( maybe on the back ) to see if it works , if not , you will need to get a primer and paint the desk with that first , then use the spray paint ! Good luck !!!

You can also use chalk paint after the Krud Kutter.

This doesn't look like a real wood desk. It looks like it has a faux wood finish over particle board. I think I would clean it well and then use a primer first. You will probably get better results.

You need to clean it well. Prime it with Kilz primer. Then spray paint. Several light coats will give you a smooth finish.

Deglosser is a must. You might also try contact paper for the top. Check out this gray/chrome/oak desk I updated

https://www.hometalk.com/diy/home-office/furniture/ugly-desk-makeover-in-a-few-hours-with-quick-veneer-and-spray-paint-33356893

First clean the desk really well, with a cleaner degreaser. Purple Power from Walmart is good, or Krud Kutter. You need to prime with a stain blocking gripper primer. Kilz or Zinser 123. Lightly sand after priming. Then paint light coats, letting it dry between coats. Follow the directions on the can for repainting time. You will need several coats