The specification Cat / Cat. (category) says something about the quality or properties of the cable and thus for which data rates you can use it.
For home applications, a Cat 5 cable is completely sufficient, especially when it comes to the connection for a TV that can only handle 100 MB anyway. Since Cat 6 hardly makes a price difference, you can also use one of these. Cat 7 is not necessary.

For home use, the flat cables are interesting because they are easier to lay.
https://www.digitec.ch/de...

Thank you very much, the answer is as clear as day and helps! Thank you