Register wp customizer

functions.php

<?php
function cpm_cc_customize_register( $wp_customize ) {

    $wp_customize->add_panel('cpm_cc_option_panel', array(
      'capability' => 'edit_theme_options',
      'theme_supports' => '',
      'title' => __('CC Options'),
            'description' => __('Panel to update theme options'), // Include html tags such as <p>.
            'priority' => 10 // Mixed with top-level-section hierarchy.
            )
    );
    $wp_customize->add_section( 'cpm_cc_product_section',   array(
      'title'       => __( 'Product Order' ),
      'description' => __('Section for Product Order Setting' ),
      'panel'       => 'cpm_cc_option_panel',
      'priority'    => 32,
      )

    );

    $wp_customize->add_setting( 'cpm_cc_product_count', array(
      'default'           => '5',
      'capability'        => 'edit_theme_options',
      )
    );

    $wp_customize->add_control( 'cpm_cc_product_count', array(
      'label'    => __( 'No. of products' ),
      'section'  => 'cpm_cc_product_section',
      'description' => __('Enter the no. of products to display'),
      'type'     => 'text',
      'priority' => 1,
      )
    );

    $wp_customize->add_setting( 'cpm_cc_product_orderby', array(
      'default'           => 'date',
      )
    );

    $wp_customize->add_control(
      'cpm_cc_product_orderby',
      array(
        'type' => 'select',
        'label' => 'Order By',
        'priority' => 2,
        'section' => 'cpm_cc_product_section',
        'choices' => array(
          'ID' => 'ID',
          'title' => 'Title',
          'name' => 'Name',
          'date' => 'Date',
          ),
        )
      );

    $wp_customize->add_setting( 'cpm_cc_product_order', array(
      'default'           => 'DESC',
      )
    );

    $wp_customize->add_control(
      'cpm_cc_product_order',
      array(
        'type' => 'select',
        'label' => 'Order',
        'priority' => 3,
        'section' => 'cpm_cc_product_section',
        'choices' => array(
          'ASC' => 'ASC',
          'DESC' => 'DESC',
          ),
        )
      );

    $wp_customize->add_section( 'cpm_cc_w_n_o_section',   array(
      'title'       => __( 'Works Well & Other Product Settings' ),
      'description' => __('Product Order Setting in Works well with and Other products section.' ),
      'panel'       => 'cpm_cc_option_panel',
      'priority'    => 32,
      )
    );


    $wp_customize->add_setting( 'cpm_cc_works_n_other_product_count', array(
      'default'           => '6',
      'capability'        => 'edit_theme_options',
      )
    );

    $wp_customize->add_control( 'cpm_cc_works_n_other_product_count', array(
      'label'    => __( 'No. of products' ),
      'section'  => 'cpm_cc_w_n_o_section',
      'description' => __('Enter the no. of products to display in Works Well With and Other Product You Mignt Like'),
      'type'     => 'text',
      'priority' => 1,
      )
    );


    $wp_customize->add_section( 'cpm_cc_product_guide_steps',   array(
      'title'       => __( 'Product Guide' ),
      'description' => __('Set the contents for Product Guide Steps.' ),
      'panel'       => 'cpm_cc_option_panel',
      'priority'    => 33,
      )
    );

    $wp_customize->add_setting( 'cpm_cc_rent_image', array(
      'capability'        => 'edit_theme_options',
      ) );

    $wp_customize->add_control( new WP_Customize_Image_Control( $wp_customize, 'cpm_cc_rent_image', array(
      'label'    => __( 'Rent Image' ),
      'section'  => 'cpm_cc_product_guide_steps',
      )
    )
    );

    $wp_customize->add_setting( 'cpm_cc_rent_textarea', array(
      'capability'        => 'edit_theme_options',
      ) );

    $wp_customize->add_control( 'cpm_cc_rent_textarea', array(
      'label' => __( 'Rent Description' ),
      'type' => 'textarea',
      'section' => 'cpm_cc_product_guide_steps',
      ) );

    $wp_customize->add_setting( 'cpm_cc_sell_image', array(
      'capability'        => 'edit_theme_options',
      ) );

    $wp_customize->add_control( new WP_Customize_Image_Control( $wp_customize, 'cpm_cc_sell_image', array(
      'label'    => __( 'Sell Image' ),
      'section'  => 'cpm_cc_product_guide_steps',
      )
    )
    );

    $wp_customize->add_setting( 'cpm_cc_sell_textarea', array(
      'capability'        => 'edit_theme_options',
      ) );

    $wp_customize->add_control( 'cpm_cc_sell_textarea', array(
      'label' => __( 'Sell Description' ),
      'type' => 'textarea',
      'section' => 'cpm_cc_product_guide_steps',
      ) );


    $wp_customize->add_setting( 'cpm_cc_keep_image', array(
      'capability'        => 'edit_theme_options',
      ) );

    $wp_customize->add_control( new WP_Customize_Image_Control( $wp_customize, 'cpm_cc_keep_image', array(
      'label'    => __( 'Keep Image' ),
      'section'  => 'cpm_cc_product_guide_steps',
      )
    )
    );

    $wp_customize->add_setting( 'cpm_cc_keep_textarea', array(
      'capability'        => 'edit_theme_options',
      ) );

    $wp_customize->add_control( 'cpm_cc_keep_textarea', array(
      'label' => __( 'Keep Description' ),
      'type' => 'textarea',
      'section' => 'cpm_cc_product_guide_steps',
      ) );


    /*Mailchimp subscribe credentials*/
    $wp_customize->add_panel('cpm_mailchimp_panel', array(
      'capability' => 'edit_theme_options',
      'theme_supports' => '',
      'title' => __('Mailchimp Options'),
            'description' => __('Panel to add mailchimp API key, list id'), // Include html tags such as <p>.
            'priority' => 10 // Mixed with top-level-section hierarchy.
            )
    );
    $wp_customize->add_section( 'cpm_mailchimp_section',   array(
      'title'       => __( 'Mailchimp Option' ),
      'description' => __('Add Mailchimp Details' ),
      'panel'       => 'cpm_mailchimp_panel',
      'priority'    => 32,
      )

    );

    //Mailchimp Api Key
    $wp_customize->add_setting( 'cpm_mailchimp_api_key', array(
      'default'           => '',
      'capability'        => 'edit_theme_options',
      )
    );

    $wp_customize->add_control( 'cpm_mailchimp_api_key', array(
      'label'    => __( 'Mailchimp Api Key' ),
      'section'  => 'cpm_mailchimp_section',
      'description' => __('Enter the mailchimp api key generated'),
      'type'     => 'text',
      'priority' => 1,
      )
    );


    //Mailchimp List Id
    $wp_customize->add_setting( 'cpm_mailchimp_list_id', array(
      'default'           => '',
      'capability'        => 'edit_theme_options',
      )
    );

    $wp_customize->add_control( 'cpm_mailchimp_list_id', array(
      'label'    => __( 'Mailchimp List Id' ),
      'section'  => 'cpm_mailchimp_section',
      'description' => __('Enter the mailchimp list id'),
      'type'     => 'text',
      'priority' => 2,
      )
    );
  }
  add_action( 'customize_register', 'cpm_cc_customize_register' );