WARNING: The model is broken Open-source advertisment system in Roblox
You can put it in your Roblox game.
You need to get the model. Get Ad.rbxm from here.
If you keep getting errors, you didn't enable HTTP requests.
For published games:
Go to Game settings > Security and enable HTTP requests.
For unpublished games:
Type the code into the command bar and hope for it to work.
game:GetService("HttpService").HttpEnabled = true