2002 Ford Taurus Cold engine

I'm disabled and it's hard to explain what's going on but going to give it a try

My wife car when she first cranks engine in the morning mostly the car feels like it's not running on all cylinders usally about 10 minutes it much better but still feel some roughness it the way it's running

It's been a good year and half since last tune-up but even then it was doing same a friend said it more likely a sensor but where do you start

Help please so I can get wife off my back

Thanks
Barepocket