Hi Elizabeth, my name is Neil, I'm an independent adviser and a Windows 10 user like you.
I'm sorry you're having these issues.
You're instincts are correct though! They are all related.
Basically your hard drive is simply too small. To run Windows 10 64 bit you need a bare minimum of 20GB of space free. This has now gone up since the May update to 32GB!
The Windows folder you refer to is the operating system files that run Windows when your computer is on. Deleting any of these files will result in corruption and your computer will be broken and unable to work. My own Windows files come to 23.2 GB.
Even though you have a 27GB of hard drive space, you then have to consider updates, other programs you are using taking up space, updates to those programs, your files, photos, documents, etc...
Basically everything you do on your computer will add things to the storage space...even browsing the web.
You state you only have 1.5Gb of free space available. I'm amazed you haven't run into more problems than you have.
Obviously updates may try and download, but there simply isn't enough room to unpack them and install them and that's why they are failing.
The only real solution to this problem is to get a new, bigger hard drive. They are quite inexpensive for say a 500GB one. Here is a link to one on Amazon as an example: https://www.amazon.co.uk/Toshiba-MQ01ABD050-500...
The only caveat with this is that you will need to install Windows 10 on it after changing out your laptop drive.
However, your copy of Windows 10 should be linked to your Microsoft Account and therefore you can download a free copy of Windows 10 from here (download the file to a USB memory stick): https://www.microsoft.com/en-gb/software-downlo...
And then install it on your new hard drive. When it comes to activation, just choose to activate later and then sign in. As soon as you sign in to your account, your copy of Windows 10 will be authenticated and activated automatically.
Let me know if you need more help.
**NOTE**
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