Q: I bought a used ipad and do not know the previous owner or id and password. is there anyway to unlock the ipad or bypass the activation to unlock the device?

No. You cannot bypass the activation code.

If you can't communicate with the previous owner, then you are out of luck.

It requires the Apple ID and password of the previous owner. If you don't have it and cannot get it, then the device is useless to you. Return it for a refund, if you can, or take it to an Apple store for an exchange provided they will help you.

Find My iPhone Activation Lock

In the future check first before buying second hand: How to check for Activation Lock before buying a used iPhone.