Before you try to implement functionalities with Mendix Studio Pro, I recommend that you first go through the online Rapid Developer Course. In this course you will learn all the basics of Mendix.
It is a self-paced way to learn Mendix and it is very useful if you want to get started with Mendix.
This is the link to the course: https://academy.mendix.com/link/paths/31/Become-a-Rapid-Developer