u/Arrow49

I know the first thing that everyone is gonna tell me is to look for already written, extensive guides on setting this up and I have done that, unfortunately I have seen contradictory information. All I have done is downloaded yt-dlp using python -m pip install --upgrade yt-dlp in the terminal. My goal is to download videos with sound. Now,

1. Is ffmpeg necessary also? Can it also be downloaded using pip?
2. Apparently, Youtube may ban users for using this and obviously I don't want that. From what I've seen you can log out of your account and use a throwaway, but let's stipulate I do that on Firefox, while still being logged in on Chrome. Then I copy the URL in Firefox and paste it into the terminal, will both accounts be tagged? I have no clue how YT would know when I copy a URL.