My iPad is locked and I can’t open it

If you're talking about the passcode to unlock your iPad's screen:

Keeping in mind that if you don't have a backup all data will be lost on that device (except those that you eventually synced to iCloud), pay attention to the specific gestures that you need to perform while connecting your iPad to a computer (Windows 10 PC running the latest iTunes version) or Mac (which can run

iTunes or Finder, depending on the macOS installed on it), and follow these instructions to re-gain access to your device:--> If you forgot the passcode on your iPad, or your iPad is disabled

If you are talking about "activation lock" (an anti-theft measure), neither we, just users like you, nor Apple can help you, sorry, unless you are the original owner and you still have the proof of purchase (receipt/invoice reporting your device’s IMEI or Serial Number). Should be this case, start your request using this link: https://al-support.apple.com/#/additional-support

Shouldn’t be this case, activation lock can be removed only by the previous owner, with the credentials that were used to activate that iPhone/iPad. Without those credentials, that device is useless to you.

You can also take a look at this support article:--> How to remove Activation Lock - Apple Support

If you mean something different, please better clarify your needs

Regards

Giulio

My ipad is visible on my mac sidebar when connected to it, but ipad will not open