Can someone get another insurance company for a different car while there original car is with a different insurance company?

Yes, but why. Perhaps you are in the process of changing companies and so you went to the new company when purchasing a new car and plan to move the other one when the policy expires in a month or so? You will not get the multi-car discount which can be substantial. Why would you want to do this? I need more information before answering more than I already have.