Debian Linux Customisation & RDP Integration

We utilize Orange Pi 3 LTS devices as cost-effective thin clients, connecting them to Microsoft Windows Remote Desktop Servers. Presently, we seek a streamlined Linux variant to serve as a thin client operating system. This system should initiate with a custom splash screen and subsequently establish a remote desktop connection to a predetermined IP address. Importantly, the IP address should be configurable solely by us through a designated configuration file, so that users will not have the ability to change it from the RDP client.

The following OSs are compatible with the Orange Pi 3LTS:
http://www.orangepi.org/html/hardWare/computerAndMicrocontrollers/service-and-support/Orange-pi-3-LTS.html

Debian and Ubuntu are the preferred choices.