The easiest way/command to open an IOS simulator from the terminal is to use the "open -a" command and specify "simulator" as the application.
open -a simulator
Upon running the command the simulator if present will automatically get launched. If not then maybe you don't have an XCode installed. Do note that when the IOS simulator is launched, the operating system will be set as the latest version for example iPhone 13 with an IOS 15. Do give it a try and cheers!
