This Magento 2 extension displays content of exception.log, system.log and debug.log files in admin panel.
Pull in the extension through Composer:
composer require "mikielis/magento2-module-log-reader:*"OR
download zipped extension and add its files to [magento root directory]/app/code/Mikielis/LogReader directory and follow listed steps from the official guide: https://devdocs.magento.com/guides/v2.3/comp-mgr/install-extensions.html