My customer gave me an iPad 9.7 with ver: 16.7.5 could you please unlock it for me

Presumably you are being prompted for your AppleID credentials - so as to satisfy an Activation Lock. You will require the AppleID an associated password that was last used to successfully activate the device - which, for the bona-fide owner, should be straightforward.

Here are the Apple support pages that outline the Activation Lock - and the only mechanisms by which it can be satisfied:

Activation Lock for iPhone, iPad, and iPod touch - Apple Support

Turn off Activation Lock – Apple Support

As you will discover, unless you are the owner of the AppleID that was last used to activate the device, you’ll not be able to defeat or bypass the Activation Lock. With documentary evidence that you are the original owner (such as sales receipt showing the serial number), Apple may be prepared to assist - otherwise they and nobody here will be able to help you.

If you have the necessary documentation, Apple have introduced a portal though which you may be able to request release of an Activation Lock:

How to remove Activation Lock - Apple Support & start an Activation Lock support request.

If you have acquired this iPad for your own use, it will need to be properly prepared/reset - and then set-up again "as new" for reuse:

What to do before you sell, give away, or trade in your iPhone or iPad - Apple Support

Did the previous owner not remove the Activation Lock?

Only the official Apple Support can help you, this is a user to user forum only.

Have a look at this article, to be able to provide them with the necessary documents:

Additional Support - Activation Lock

Sorry, we can't access any data or settings from other fellow users.

Only the official Apple Support can help you unlock the device.

Click on this article and follow the steps mentioned:

Additional Support - Activation Lock