Set environmental variables from shell script in Jenkins pipeline

Question

I have a requirement where I have a shell file (init.sh) which sets environmental variables based on conditions.

My pipeline looks something like this

pipeline {
    agent {
        kubernetes {
            label 'test'
        }

    environment { 
        token = credentials('xyz')
    }

    stages {
     stage('test'){
                  container('test') {
                  sh """#!/bin/bash
                  printenv
                  """
              }
     }
    }
}

Is it possible to set the env(s) from the init.sh file which can be used inside the container as well?

Can anything be done in the environment block?