I forgot password via guided access, how i can reset this? ipad is offline

Devices with a physical Home Button

The only way to get out of Guided Access is to press the Home and Power button together for 15 seconds. This should turn off Guided Access by forcibly rebooting your device. Once your device is restarted, you can then go to Settings > Accessibility > Guided Access > Guided Access - and turn off Guided Access if needed.

Use Guided Access on iPad - Apple Support

Use Guided Access with iPhone, iPad, and iPod touch - Apple Support

Devices without a physical Home Button

For iPad’s without a physical Home button, you’ll need to follow a different button sequence…

1. Press and quickly release the volume button nearest to the top button.
2. Press and quickly release the volume button farthest from the top button.
3. Press and hold the top button.
4. When the Apple logo appears, release the top button.

if you mean the passcode then connect the ipad to a computer using the cable and read

If you forgot your iPad passcode - Apple Support