Fetch data from multiple tables in a Magento admin grid

Collection.php

<?php
namespace Macademy\Minerva\Model\ResourceModel\Faq\Grid;

class Collection extends \Magento\Framework\View\Element\UiComponent\DataProvider\SearchResult
{
    protected function _initSelect()
    {
        parent::_initSelect();
        
        // Add your join statements here
        $this->getSelect()->joinLeft(
            ['second_table' => $this->getTable('your_second_table')],
            'main_table.foreign_key = second_table.id',
            ['second_table_column1', 'second_table_column2']
        );
        
        // You can add more joins if needed
        $this->getSelect()->joinLeft(
            ['third_table' => $this->getTable('your_third_table')],
            'main_table.another_foreign_key = third_table.id',
            ['third_table_column1']
        );
        
        return $this;
    }
}

di.xml

<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:ObjectManager/etc/config.xsd">
    <virtualType name="Macademy\Minerva\Model\ResourceModel\Faq\Grid\Collection" type="Macademy\Minerva\Model\ResourceModel\Faq\Grid\Collection">
        <arguments>
            <argument name="mainTable" xsi:type="string">macademy_minerva_faq</argument>
            <argument name="resourceModel" xsi:type="string">Macademy\Minerva\Model\ResourceModel\Faq</argument>
        </arguments>
    </virtualType>
    
    <type name="Magento\Framework\View\Element\UiComponent\DataProvider\CollectionFactory">
        <arguments>
            <argument name="collections" xsi:type="array">
                <item name="macademy_minerva_faq_listing_data_source" xsi:type="string">Macademy\Minerva\Model\ResourceModel\Faq\Grid\Collection</item>
            </argument>
        </arguments>
    </type>
</config>