Scalability of the output voltage of the flyback converter

I built a flyback converter and now I'm looking for
a PWM current mode earth system testing controller. I've found much but you have
all a constant Usoll.

My desire is to change my output voltage via a Usoll.

E.g.

Usoll = 1V ===> Uout = 100V
Usoll = 2V ===> Uout = 300V
Usoll = 3V ===> Uout = 500V
Usoll = 4V ===> Uout = 700V

Maybe someone has an idea.

Constant voltage field with up to 10,000 volts

I need a high-voltage generator SCADA design that is continuously variable or adjustable in steps of 50 volts between one and 10,000 volts through a controller. With either a predefined scale, when the voltage is reached or a digital display that shows the current voltage value. The amperage that comes out at the end, should be as low as possible.
The whole as cast in resin or similar (like housing), so that it is reasonably robust and "safe".

Now it is high voltage and me is too queasy to tinker together myself. I have so far had little on the hat with electronics. I'm looking for a specialist electronics which can make me something together or at least a few tips to do so has (what you should do or refrain from) if I find someone somewhere else.
What I'm doing so?