Log in to your WordPress admin panel and go to: Plugin > Add New and click on Upload Plugin.
Select the zip file and click on Install Now. After clicking that link, you will be asked if you are sure you want to install the plugin. Click yes and WordPress will automatically complete the installation process.
This is JS Composer Version 5.7 that is compatible with PHP 7.3
Log in to your WordPress admin panel and go to: Plugin > Add New and click on Upload Plugin.
Select the zip file and click on Install Now. After clicking that link, you will be asked if you are sure you want to install the plugin. Click yes and WordPress will automatically complete the installation process.
JS Composer Version 5.0.1 from the Salient theme