New to Sims 4 wanting to build extensions to my house how do I manage this?

[DragonMom]

  I want to make my house bigger how do I add on more rooms (extensions)? I am playing on a PS4.

[MrsFlynn]

Building is similar on console as it is on PC, except for the controls are different.

Here are some building tutorials to start. I'm sure if you search you can find a lot more.

Sims 4 Building Basics: Build Mode Guide for Beautiful Homes
https://www.carls-sims-4-guide.com/tutorials/building/houses.php

Sims 4 Tutorial - #3 - Understanding How Rooms Work
https://www.youtube.com/watch?v=NSM2N070zxE