Dove, I have a cordless mouse at work. Yes, you do plug the cord into the old port, assuming that it is the same type, ie USB, etc. Try turning off your computer and turning it back on then your computer may recognize the new mouse. There should have been some software to download onto your computer. This happened to my brother today, his computer would not recognize his new scanner. Good luck!!
Do what you can, with what you have, where you are.
26th president of US (1858 - 1919)