400 bad request with trying to get user id or follower list

curl -H ‘Accept: application/vnd.twitchtv.v5+json’ -H ‘Client-ID: xuvnniaiv7jupqbb4wdfo2rbbhlefv’ -H ‘Authorization: Bearer <client_code>’ -H 'Authorization: OAuth '$token

Should be just

curl -H ‘Client-ID: xuvnniaiv7jupqbb4wdfo2rbbhlefv’ -H ‘Authorization: Bearer <client_code>’

You are sending both Kraken and Helix headers. for all requests. Shouldn’t be a problem but we can clean our your headers to JUST Helix headers

use helix get users

There is no follow request in your code.