Not able to restore my IPAD

Apple doesn’t explicitly list error #5, however, similar errors are often linked with Anti-Virus and/or firewall software running on the host computer.

While you do so entirely at your own risk, try temporarily disabling your AV/Firewall software - and then repeat your attempt to restore your iPad.

Otherwise, you may need to seek assistance directly from from Apple Support. You can contact the Support Team using the Get Support link at top-right of this page. Alternatively, if you have access to another Apple device, you can initiate and manage your support cases using the excellent Apple Support App. If not already installed, the App can be downloaded from the App Store:

https://apps.apple.com/gb/app/apple-support/id1130498044

You might also visit the Genius Bar at your local Apple Store or Apple Authorised Service Provider (AASP) - where the technicians will be able to provide assistance:

Genius Bar Reservation and Apple Support Options - Apple

With no details of precisely what you have already tried - or details of the issue that you are attempting to recover from - it is extremely difficult to provide specific guidance.

These support pages are perhaps good starting points:

Restore your iPhone, iPad, or iPod touch from a backup - Apple Support

Restore your iPhone, iPad, or iPod to factory settings - Apple Support

If you can't update or restore your iPad - Apple Support

iOS update and restore errors - Apple Support

If you remain unable to resolve your current problem, you will need to provide more information as to what has happened - and what you have actually tried in attempting to resolve the problem. Details of any errors that you have seen will be helpful to contributors.

Have you tried putting the iPad into recovery mode? If you haven’t, you should follow the instructions here: If you can't update or restore your iPad - Apple Support

Do you have another Mac or Windows PC you could use? If so trying it there could fix it. You could also try with another cable.