Magento 2: How to get data from controller to block/view

One approach is to use the registry so in your controller class you put it in the registry, and then in your block you can retrieve it.

<?php

namespace <Vendor>\<ModuleName>\Controller\Index;

use Magento\Framework\App\Action\Action;

class Index extends Action
{
    protected $_coreRegistry;

    public function __construct(
        \Magento\Framework\App\Action\Context $context,
        \Magento\Framework\Registry $coreRegistry,
        \Magento\Framework\View\Result\PageFactory $pageFactory
    ) {
        $this->_coreRegistry = $coreRegistry;
        $this->_resultPageFactory = $pageFactory;
        parent::__construct($context);
    }

    public function execute()
    {
        $this->_coreRegistry->register('foo', 'bar');
        return $this->_resultPageFactory->create();
    }
}

Then in your block you can do;

<?php

namespace <Vendor>\<ModuleName>\Block;

use Magento\Framework\View\Element\Template;

class Moo extends Template
{
    protected $_coreRegistry;

    public function __construct(
        \Magento\Framework\App\Action\Context $context,
        \Magento\Framework\Registry $coreRegistry,
        array $data = []
    ) {
        $this->_coreRegistry = $coreRegistry;
        parent::__construct($context, $data);
    }

    public function getFoo()
    {
        // will return 'bar'
        return $this->_coreRegistry->registry('foo');
    }
}

Obviously you need to get your block on the page in the first place but this should give you a good start.

You should not passing data from Controller Action to View. Use block to for passing data to View (template engine).