Your App may not be fully compatible with your iPad model and installed version of iPadOS.
You should seek assistance from the developer of the App with which you are having difficulties. It is not uncommon for an App to require an update, by the developer, to address issues.
If all Apps exhibit the same issue, then it may be necessary to reset your iPad.
In the first instance, after attempting a forced restart, a simple reset of All Settings may suffice:
Settings > General > Reset > Reset All Settings - this will not erase any data from your iPad.
If this doesn’t resolve the issue, then a full reset may be required. After ensuring that you have a current iCloud or iTunes backup, fully reset the iPad:
Settings > General > Reset > Erase all Content and Settings - this reset will erase all data.