Create WooCommerce Product Tab with content from Product Meta custom field

woocommerce-custom-product-tab-and-meta-field-content.php

<?php
// add this code to the functions.php file of your Theme or Child Theme

/*
 * Add Custom tabs to WooCommerce products which contain content stored in custom fields (product postmeta fields)
 * This example is adding 3 tabs. Product Instructions, Size Chart, and Tech Specs
 * There are 2 pieces that are needed:
 * 1. Declare the tab
 * 2. Declare the contents of the tab
 * Recommended to use ACF (advanced custom fields plugin) to managage the tab content per product.
 */
 
 
 // 1. Declaring the tabs
	add_filter( 'woocommerce_product_tabs', 'bhww_woo_extra_tabs' );
	
	function bhww_woo_extra_tabs( $tabs ) {
	// requesting the meta fields
		global $post;
		$product_instructions = get_post_meta( $post->ID, '_instructions_tab', true );
		$size_chart  = get_post_meta( $post->ID, '_size_chart_tab', true );
		$tech_specs  = get_post_meta( $post->ID, '_tech_specs_tab', true );
	// checking if the meta fields have content. If no content, the tab doesn't show on the product
	// checking first tab
		if ( ! empty( $product_instructions ) ) {
		
			$tabs['instructions_tab'] = array(
				'title'    => __( 'Instructions', 'woocommerce' ),
				'priority' => 15,
				'callback' => 'sls_instructions_tab' // refers to function below, which gets the content
			);
			
		}
		// checking second tab
		if ( ! empty( $size_chart ) ) {
		
			$tabs['size_chart_tab'] = array(
				'title'    => __( 'Size Chart', 'woocommerce' ),
				'priority' => 16,
				'callback' => 'sls_size_chart_tab' // refers to function below, which gets the content
			);
			
		}
    // checking third tab
		if ( ! empty( $tech_specs ) ) {
		
			$tabs['tech_specs_tab'] = array(
				'title'    => __( 'Tech Specs', 'woocommerce' ),
				'priority' => 17,
				'callback' => 'sls_tech_spec_tab' // refers to function below, which gets the content
			);
			
		}
		
		return $tabs;
	 
	}
	// Getting the content that is stored in the meta fields to display within the tab
	// Tab 1 content
	function sls_instructions_tab() {
	
		global $post;
		$product_instructions = get_post_meta( $post->ID, '_instructions_tab', true );
	 
		if ( ! empty( $product_instructions ) ) {
		
			echo '<h2>' . esc_html__( 'Product Instructions', 'woocommerce' ) . '</h2>';
			
			// Updated to apply the_content filter to WYSIWYG content
			echo apply_filters( 'the_content', $product_instructions );
			
		}
	 
	}
	// Tab 2 content
	function sls_size_chart_tab() {
	
		global $post;
		$size_chart = get_post_meta( $post->ID, '_size_chart_tab', true );
	 
		if ( ! empty( $size_chart ) ) {
		
			echo '<h2>' . esc_html__( 'Size Chart', 'woocommerce' ) . '</h2>';
		
			// Updated to apply the_content filter to WYSIWYG content
			echo apply_filters( 'the_content', $size_chart );
			
		}
	 
	}
  // Tab 3 content
	function sls_tech_spec_tab() {
	
		global $post;
		$size_chart = get_post_meta( $post->ID, '_tech_specs_tab', true );
	 
		if ( ! empty( $size_chart ) ) {
		
			echo '<h2>' . esc_html__( 'Tech Specs', 'woocommerce' ) . '</h2>';
		
			// Updated to apply the_content filter to WYSIWYG content
			echo apply_filters( 'the_content', $size_chart );
			
		}
	 
	}


?>

The easiest way to do this, is to use Advanced Custom Fields (plugin). You can set up text boxes or what ever field works best for you to edit the content stored in the custom field.

If you've never used ACF to add editable fields in WP Admin pages, they have great tutorials on their website.
https://www.advancedcustomfields.com/resources/adding-fields-posts/

Hopefully that's not too vague. If you can't figure it out with this but of info, let me know.