Please explain how that post helps the OP?
The OP has a "storage" problem, not an OS problem!
If you're upgrading directly from Windows 10 to Windows 11, the download size is about 3.5 GB. And, you need to make sure that you have at least 64GB of free space. If you install Windows 11 using an .ISO file, plan on having 25 GB of free space at least.
Windows 11 Size: How Much Space Does It Take Up - EaseUS