My iPad storage plan

What is strange? Your iPads have different storage amounts, but both can sync data to iCloud if signed in, meaning that changes on one will be reflected on the other (which may or may not be what you want). And tap what button?

If youi want the online 50GB to be available to a different iPad, sign out of iCloud on the one it's on, and sign into iCloud on the other one.

The result of this is that data on the second iPad will be uploaded to iCloud instead of data from the first one. But this does not 'affect' the iPad. You say the storage on the school uPad is 32GB: it will remain 32GB after you have made the change. The storage on iCloud does not 'affect' the iPad: it is just that it's available for uploading/syncing. The 32GB cannot be increased and if it is full signing into iCloud won't make any difference.

The 50GB storage is online at iCloud and is accessible to any device signed in there for syncing data. It is not actually on your iPad: the storage on iPads cannot be increased.

Please see this thread: https://discussions.apple.com/thread/250270641 - try the last post's suggestion first.