The applications are meant to resides in the Applications folder.
On macOS, when you save a file into the Applications folder, then decide to move it elsewhere, you will copy a link to that file (you will not move the file).
Also, using a BinaryStream to save text data is not what most of people will do (and if some will do that, they will have a very good reason).
As far as I understand, these are numeric values, save them as is (and read them accordingly, because you will read them at a moment or another).
You do not know how to transform a text data into a numeric data ? Look at the documentation (http://docs.xojo.com/Val and read the See Also paragraph).
At last, you can save the data in a file silently: avoid the dialog display as it is said earlier (above).
The world current situation is stressing, so I can understand you.
In the future, before asking questions here (or waste time searching how to in Xojo), lookhow things are done in the OS (in the above case, TextEdit in macOS, WordPad in Windows): where they want to store the data by default for this example.
These are advices, clues, nothing else.