Because the same blank white window appears when using Save, Save As, or Export in both Office and Adobe, I would first determine whether the problem is specific to those applications or is affecting macOS more generally.
I would start by opening TextEdit, creating a small document, and choosing File > Save.
Save the test document to a local folder such as Documents. If TextEdit produces the same blank white window, that would suggest the problem is not limited to Office or Adobe.
If TextEdit saves normally, that would narrow the problem toward the affected applications or their interaction with macOS.
I would also test saving from Office and Adobe to a local folder rather than OneDrive, iCloud Drive, Dropbox, Google Drive, a network drive, or another cloud location.
If saving locally works but saving to a cloud or network location does not, that would provide an important clue.
If the problem continues, the next step would be to test the Mac in Safe Mode.
On an Apple-silicon Mac, shut down the Mac, press and hold the power button until the startup options appear, select the startup disk, then hold Shift and choose Continue in Safe Mode.
Once in Safe Mode, repeat the Save test. Apple notes that Safe Mode can help determine whether software that loads during startup is contributing to a problem.
Apple: Start up your Mac in safe mode
If the problem still occurs, Disk Utility First Aid would be another reasonable step, particularly if there are other indications of storage or filesystem problems.
Apple: Repair a Mac storage device with Disk Utility
Before doing anything more invasive,
I would make sure important data is properly backed up.
For irreplaceable data, I recommend a 3-2-1 backup strategy: three copies of the data, using two different types of storage, with one copy kept off-site. Time Machine provides a useful Mac backup and recovery option, while a separate solution such as Carbon Copy Cloner can provide an additional layer of protection.
Apple: Time Machine
Bombich Software
How to schedule a backup
At this point, I would not reinstall Office or Adobe.
The TextEdit, local-folder, and Safe Mode tests should provide much more useful information about where the problem is occurring before making changes to the applications.