Dear @Mariam_Kashkash ,
Sorry for the delay in replying!
I see that you’ve referred to a fairly old topic which contains an old way of obtaining Reachy by simulation and which is no longer active today.
To control a Virtual Reachy, here’s the link that tells you the 2 ways to do it (Unity or Gazebo): About the Simulation & Virtual Reachy category
I hope you find this useful.