The Nintendo Switch offers the users three different modes of play, as well as have a versatile Joy-Con controller. The Nintendo Switch Pro is sold separately.
This guide will instruct you with the setup of the Nintendo Switch as well as give you a detailed aspect of the controller.

Complete Nintendo Switch Controller Guide and Setup
Here is the complete guide for Nintendo Switch Controller which will help you from attaching the controller till removing it and even holding it.
Attaching the Joy-Con Controllers
When in the handheld mode, players can enjoy the Nintendo Switch controller game with the Joy-Con controllers attached to the console. If you wish to connect them to your console, just align the controller on the rails properly on both the sides and slide them down till you hear the click. You should attach your Joy-Con controllers properly. Put your left and right Joy-Con controllers on either side of the console correctly. To identify them, the right Joy-Con will have the + Button, and the left Joy-Con will have the – Button. You can attach a total of 10 Joy-Cons to your controller.
Removing the Joy-Con controllers
To remove the Joy-Con controllers from your Nintendo Switch console, push the button present on the backside of the controller and drag it upwards. Doing this will keep the Joy-Con paired to your Nintendo Switch, and you can use it wirelessly. You can also charge them up when they run out of battery.