New ipad pro 2021 freezes om home screen, when trying to open app, only a white screen appears.

Are you having difficulties with launching a specific App - or are all Apps similarly affected?

Single App affected

Starting with the least invasive action - if only a single App is having problems - initially try offloading (or deleting) the offending App. Offloading preserves App-data, while deleting the App removes both the App and any associated data:

https://www.idownloadblog.com/2022/01/06/how-to-offload-app-iphone-ipad/

Delete apps on your iPhone, iPad, and iPod touch - Apple Support

After offloading/deleting, perform a forced-restart of the iPad:

• On an iPad with a Home button: Press and hold the top button and the Home button at the same time. When the Apple logo appears, release both buttons.
• On other iPad models: Press and quickly release the volume up button, press and quickly release the volume down button, then press and hold the top button. When the Apple logo appears, release the button.

After restarting the iPad, you can re-install the offloaded/deleted App from the App Store. When reinstalled, try to launch the App; if the problem has been resolved, there’s nothing more for you to do.

All Apps affected

Perform the forced restart as described above.

Issue Unresolved

In the unlikely event that the problem remains unresolved, you might consider a reset of your iPad settings. While your data should not be affected, as a precaution, ensure that you have a current iCloud or iTunes backup of your iPad:

How to back up your iPhone, iPad, and iPod touch - Apple Support

Once you have ensured that you have a backup, you can reset your iPad settings:

Settings > General > Transfer or Reset iPad > Reset > Reset All Settings

If the issue affects all Apps - and the problem still remains unresolved - it may be necessary to take more drastic action. Only if all other avenues have been explored, you should perform a Factory Restore of your iPad:

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

After performing the Factory Restore, you can restore your data from your iCloud/iTunes backup. At conclusion of the Factory Restore process, you will be presented with the opportunity to restore your data - otherwise, you can do so manually:

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

To rule out a software issue, set your iPad back to factory settings, using your computer.

Then set it up manually, without using the backup see if you can open the default apps..

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

If it works again, restore from the latest backup to get all your data and settings back.

Before you set it back to factory settings, try to force restart it, in case it is only a minor issue:

Restart iPad - Apple Support