Somewhere, you are trying to print the character “\u00007” which I’m not sure what that is. “\u0007” is the BELL character, so I don’t know where that extra 0 is coming from.
The fact that you are printing a new line between each set of samples should offer some clue…there should be no blank line between your lines of values.
There are a number of ways to get sample values to Edge Impulse. With slower samples (e.g. not audio or data), you can use the data forwarder or pre-compiled firmware + Edge Impulse CLI (for supported boards). You can also save your values in CBOR, JSON, or CSV files and upload them directly to your project in Edge Impulse.
For my projects, I like to save things as CSV files (either locally on an SD card or send them to my computer over USB). I have an example here showing how to transmit CSV data with Arduino and capture it over USB with a Python script: https://github.com/edgeimpulse/example-data-collection-csv
Hope that helps!