Welcome to GPLDL - we are still beta - please report any bugs via the contact form.
@Barbara You can use this plugin: You can use this plugin: https://wordpress.org/plugins/easy-theme-and-plugin-upgrades/
This plugin is best for manual updates and handles everything automatically. You just need to go to “Add Plugins” => Upload Plugin and then browse the latest plugin file.
It will handle the remaining things :)