There is more than one way to start a planted tank. If you are starting a non-planted tank you do have to cycle it before adding fish, but if you are going to plant the tank heavily with fast growing stem plants, as you should be, you can plant those before filling the tank with water. Then fill the tank with water, add the lights, begin light fertilizing, and wait a week or so to make sure the plants have started growing well, before adding just a few fish, preferably the hardiest ones that you intend to keep. Limit the time the lights are on to 4-6 hours a day for a week too, to discourage any algae from starting. Then increase the lights on time by half hour at a time, a few days apart, until you have that time up to 8 hours.
If you then want to entertain yourself, use your test kits to see how they work. Then ignore the readings. You can worry about that later.
This is the way I start a tank.