Will putting hooks in the wood to hang lights or a fan harm the wood?

I actually attached a 2x4 all the way across the center and used 2x4 brackets with metal plates on the 2x4. The brackets attached to the main beam and this gave me a great place for a ceiling fan. I did not hardwire it to my house but put a plug to an outlet but wired it after with pvc conduit so I can unplug it, that way there is no electrical inspection since it isn’t attached to the house.

Hi Shane, While our gazebos were not designed specifically to have ceiling fans attached, we have engineered the structure to withstand marketing-leading load up to 50 lbs/square foot…or total weight 6391 pounds. Adding a ceiling fan will not pose a threat to the stability of the structure. However, be aware that driving hardware into the roof could penetrate the roof and create an area for rain penetration.