Zend certified PHP/Magento developer

Can Microsoft Windows Server 2022 Remote Desktop Services User Cals be used on Windows Server 2019 Standard?

My friend already has Windows Server 2019 Essentials but no RDS licenses yet. He wants to use several (more than two) parallel Remote Desktop connections. It seems it is not possible on Windows Server 2019 Essentials, unfortunately. Is this correct?

Does my friend need a Windows Server 2019 Standard edition license?

While buying RDS licenses, would it be wise to buy Windows Server 2022 RDS licenses to have them expire later than 2019 EOL (Jan 2029) – but will they work with Windows Server 2019 Standard?