I have found this module :

https://github.com/bitExpert/magento2-force-login

But this show errors in Frontend -

1 exception(s): Exception #0 (ReflectionException): Class BitExpert\ForceCustomerLogin\Controller\LoginRouter does not exist Exception #0 (ReflectionException): Class BitExpert\ForceCustomerLogin\Controller\LoginRouter does not exist #0 C:\wamp64\www\sk\vendor\magento\framework\Code\Reader\ClassReader.php(19): ReflectionClass->__construct('BitExpert\\Force...') #1 C:\wamp64\www\sk\vendor\magento\framework\ObjectManager\Definition\Runtime.php(44): Magento\Framework\Code\Reader\ClassReader->getConstructor('BitExpert\\Force...') #2 C:\wamp64\www\sk\vendor\magento\framework\ObjectManager\Factory\Dynamic\Developer.php(48): Magento\Framework\ObjectManager\Definition\Runtime->getParameters('BitExpert\\Force...') #3 C:\wamp64\www\sk\vendor\magento\framework\ObjectManager\ObjectManager.php(56): Magento\Framework\ObjectManager\Factory\Dynamic\Developer->create('BitExpert\\Force...', Array) 

Any options to force login in catlog and product page without module