Remove android and put on ubuntu "help!

Hello Team,
Hope this message goes to the correct location
First off I am going to start with saying that in no way am I experienced with arm processors
I am an old school Unix /Linux systems engineer (IBM Main frame TAndem Nonstop , Unix/linux
Now my issue
I have a SEALED all in one device that has a rk3588 inside
The board I am told is based on Rockchip RK3588 Development Board EVB1
That is all the information that I was given

It was pre loaded with android 9
We need this to run linux Ubuntu
The device has no Sd card module
It has two standard usb 3.0 one Usb C two HDMI in/out and rj45
I have figured out how to get rkdev tool to recognize this device and that is as far as it goes .

Can any one guide me how to get linux onto this system so I can remove android?

Thank. you