I was given my ipad from my dad and do not know his Apple ID or password?

As very close family, you will likely have sufficient knowledge to recover the AppleID and associated password. The following advice is written from the perspective of the owner, but you’ll get the idea...

If your device is Activation Locked, this help page will provide most of the information that you’ll need:

https://support.apple.com/en-us/HT201365

If you have forgotten your AppleID or associated password, these can be recovered here:

https://iforgot.apple.com

To recover your credentials, you’ll need access to one of the following:

• Your primary email address mailbox that corresponds with your AppleID
• Any of the secondary/recovery email addresses that should be configured for your AppleID account
• Any of the trusted telephone numbers (fixed line or Cellular/Mobile) that are associated with your AppleID

Unless you AppleID account has not been fully/correctly configured, or has been seriously neglected, recovery of the AppleID and password should not be difficult.

More information about recovery of your AppleID:

https://support.apple.com/en-us/HT201354

More information about recovery of your AppleID password:

https://support.apple.com/en-us/HT201487

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

If you are unable to get into the iPad with the help provided above, this Apple Support Document, is about getting access to deceased family member devices --> How to request access to a deceased family member's Apple accounts - Apple Support

Show him this If you forgot your Apple ID - Apple Support