Hi there and welcome
As the first step can you please hold the home and power buttons for about 10 seconds until you see the Apple Logo and then release.
Let the iPad restart and tell me if you are still being asked for the passcode please.
Let me know the results.
You will have to reset the iPad , there is no other way to remove this.
To do the reset
Connect the iPad to the computer and open itunes
Hold the power and home button down until you see
"iTunes has detected an iPad in recovery mode..."
Click Restore iPad , let this complete and it should now work
I can also do these steps for you, and have made a request via Additional Services. This is optional, and if you choose to do this, I can, with your permission, remote into your computer while you watch and do all these steps (and deal with any problems that arise during them) for you. Or if you do not choose to take this service, we can continue here. This is no problem at all. Just let me know please.