Desperately need a recomendation

Could someone please recommend to me, a device that i need to control the top platform of a robot to remain level ( 1 axis ONLY! )…
I need to be able to control the angle and the speed of the motor. The output i need is for a 12v dc motor, only a few amps.
Any and all recommendations are welcome.
FYI. The more simple the better.
Thank you.

Sorry, but we are not focuses much on robotics. We focus heavily on IoT internet connected hardware.
Thanks for your post though,