Yes and no.
You CAN play the majority of the Wii U's games just on the game pad, but, it doesn't function like the Switch.
The Wii U controller, unlike the Switch, is still very much just a controller; you have to be within a certain distance from the console, or the console starts failing to detect the controller and the game auto-pauses until you're in range again.
So basically, as long as you don't mind having to be within a certain distance of the main console unit, the Wii U should be just fine for your at-home play, even if you only want to use the game pad.