Limited disk space keeps being filled on Windows 10

I'm having problems on my PC due to a lack of disk space. Now, I do have a lot of disk space on the computer, on the HDD where I store files and programs, mapped to the D: drive. The operating system and any programs I cannot custom install are on a much smaller SSD, mapped to the C: drive.

It is this C: drive which is running into a problem of constantly being full, and it isn't very clear what is taking up so much space. At first, I thought of the usual suspects of deleting large, obsolete documents and programs, until I remembered that all these are located on the D: drive, so deleting them would have no effect on freeing up space on C: .

This is where things get bizarre, because deleting documents somehow does free up space on C:, despite the document being kept on D:. And now that C: is completely full, I am getting an error message on Microsoft Office saying they can't save documents due to the disk being full, except I'm not saving the document on C:, so there is no way the disk could be full.

Is there some kind of cache on C: being created by programs I've installed in D:, like Microsoft Office? If so, how do I stop them doing that or tell them to move it to D: so the C: drive doesn't keep getting full?

This is frustrating because my computer has been partitioned this way since the day I bought it, and I had a lengthy conversation about it online but people were emphatic that I should have no problems keeping all data on the HDD, while keeping the operating system on the SSD, and yet these space problems still plague me a year later.

I know it is a bit of an open question but if I could just have a solution for Microsoft Office alone that should help a lot. I've added screenshots from the program WinDir to illustrate what I mean, that it isn't very clear where this "bloat" is coming from.

Edit: It seems my comments are being deleted, in which I explain that the provided answer didn't help and I actually didn't recover disk space, and I was requesting more information/better answer. Also, one comment that was deleted was suggesting that I should repartition the disk to give Windows more space, which I think is a good idea, and I just asked how much space Windows should have (given that 60 GB is too small).

The Windows partition takes up the largest space and should be attacked first.
Check and delete the contents of:

• C:\Windows\Temp
• C:\Windows\Minidump
• C:\Users\USERNAME\AppData\Local\Temp

Skip any files to which you don't have the permissions to delete.

Second, empty the Recycle Bin by right-click on its desktop icon.

Third, if you use System Restore, reduce its space. See the article
Make System Restore in Windows 10 Use Less Disk Space.
You need about 2 GB for each restore point, so don't reduce it below 4-5 GB.

Fourth, check that the page-file is not larger than your RAM, or move it entirely to the D: drive.
See How to Change the Windows Pagefile Sizes.

These manipulations should free several gigabytes of disk space on C:.