Yes, it's at the top of the GO app in camera view. Both signals have bars meters representing the signal strength.
It's important to realize that you can sometimes lose video and still have control of the craft. In this case you can ascend to a higher elevation to regain the video link. You'll know if you have control, the LED light on the RC will be green instead of red. Red means no control and it then automatically enables RTH.
If you lose control signal first, this disconnects the video signal automatically and the craft will enable RTH. I've noticed this is a habit of P4 more than P3P, where the control signal disconnects first with little warning from the signal strength bars. Whereas with P3P I will always lose the video feed first and still have a good control signal connection, allowing me to ascend to regain the video signal. This occurs because the GL300C controller that comes with the P4 is weak, the weakest lightbridge controller from DJI to date, in terms of signal transmission strength. You really need to boost the signal of the GL300C controller to be happy, IMO, or use a different model controller from P3P or Inspire, which are both compatible with P4 craft.