I sold my ipad and didn't erase my icloud connection. How do I get it disconnected to my icloud?

See the following from How to remove Activation Lock - Apple Support

Unlock on the web

To remove Activation Lock from a device that's not in your possession, follow the steps below. If you purchased a device that's protected by Activation Lock, ask the previous owner to follow these steps. 

1. From a web browser, sign in to iCloud.com with your Apple ID.
2. Go to Find iPhone.
3. Click All Devices at the top of the screen.
4. Select the device that you want to remove from iCloud.
5. Click Erase [device]. Select Next until the device is erased. 
6. Click Remove from Account.

To begin the setup process, restart the device.