Unfortunately, without the iPad Passcode, you’ll not be able to recover access to the iPad without losing all locally stored data. The Passcode cannot be independently reset.
If your iPad is disabled, or the Passcode is unknown or forgotten, you’ll need to follow this process:
If you’ve forgotten the passcode on your iPad, or your iPad is disabled – Apple Support
You’ll need access to either a PC (with iTunes installed) or a Mac (with iTunes or Finder - as appropriate for the installed version of MacOS). The procedure will erase all locally stored data - however, you will be able to later restore the iCloud or iTunes backup if you have one.
You’ll also need the AppleID and associated password. If these have also been forgotten or are equally unknown, they can be recovered here:
https://iforgot.apple.com
To recover your credentials, you’ll need access to any one of the following:
- The primary email address mailbox that corresponds with your husband’s AppleID
- Any of the secondary/recovery email addresses that should be configured for the AppleID account
- Any of the trusted telephone numbers (fixed line or Cellular/Mobile) that are associated with the AppleID
Unless the AppleID account has not been fully/correctly configured, or has been seriously neglected, recovery of the AppleID and password shouldn’t be too difficult.
More information about recovery of your AppleID:
If you forgot your Apple ID - Apple Support
More information about recovery of your AppleID password:
If you forgot your Apple ID password - Apple Support
When you recover access to your credentials, you would be well advised to log-in to your AppleID account from a web browser - and verify/update any email addresses and trusted telephone numbers:
https://appleid.apple.com
Having recovered access to the iCloud account - and the iPad - you’ll hopefully confirm existence of an iCloud backup - and can therefore restore most (if not all) the previously stored data.
If all else fails, you can apply to Apple for access to your late husband’s account. The process is protracted with no guarantee of success. I recommend that you exhaust the self-help options before attempting to pursue this avenue.
How to request access to a deceased family member's Apple accounts - Apple Support