The stick is just like any other PC, with low storage. If you have been maintaining the storage, and not installing all sorts of apps, you should be fine.
On my STCK1A32WFC, with W10 Pro, I have 18gb FREE.
So, you have to cleanup, uninstall apps, and do what is necessary to increase free space. In addition to the Disk Cleanup, go to start, settings, system, storage, temporary, and check all boxes and remove.
In the future, you can use an external drive, usb stick, and even a mSD card for storage. However, it is up to you to put forth the effort to manage your storage. Your stick did not get like this overnight.
I make the install media from Microsoft on a USB stick.
Do you have your key, or did your stick come pre-installed with W10 Home?
My stick came with W8.1 with bing (whatever the heck that was). I did a fresh install with W10 Pro 1507, deleting all partitions and letting it install. That was five years ago.
I have done all of the upgrades since then as one would normally do the upgrades. I understand now that Microsoft wants to reserve more space for upgrades, but it has not affected me.
If you do not have a W10 Pro 32-bit key, windows should select the version based on the key in your stick firmware.
I have very few apps on the stick, and use it mainly for netflix on a dumb tv.