Basic setup cadence etc

I have a basic setup so used it today for the first time which i loved, however the problem i have before i go for a SMART trainer is this.

I have a cycle Ops fluid 2 paired with a Garmin Cadence and Speed sensor.

So on the training it tells me to do 130 Watts then just as it tells me this says cadence of 90-100.

So i presume i need to keep my cadence between this and at 130 Watts ?

So if i was to get a SMART trainer would I still have to keep an eye on the cadence as well or am i missing the point all together?

Using a Smart trainer, you have to keep to the cadence - this is after all something you control. With a Smart trainer you can work in Ergo mode though - in which case the software keeps the resistance at the right level, regardless of the cadence you are keeping.