Becuase Twitch doesn’t provide a way to do that.
The Console doesn’t have a “give me a token for my account” system.
There are third party third party token generators or you can just grab/write a script.
I have a “one page” PHP example on https://github.com/BarryCarlyon/twitch_misc/tree/main/authentication/user_access_generator which might save you timed, (or a nodeJS one if that takes your fancy)
You’ll need to generate a token via the web flow.
Then when that token dies use the refresh token to get a new token.
If the refresh token is dead then you’ll need to web flow again