Change scene by tapping a button in unity 5 UI System

Hi everybody, i have a little problem! I should make a main menu, and when i press the start button it should bring me with The ApplicationLoadlevel function to the first level of the game. The question is: How Can i do that? In the button panel i should do something with that OnClick On the bottom of the menu, but i don’t know exactly what. I hope you understood, my english is terrible XD. Is pretty urgent, so whoever knows how to do it please let me immediatly know!

To use the OnClick() box, simply attach a script to the button containing a function called LoadFirstLevel() or something like that. Then, in the inspector in the OnClick() box, press the plus to add an event to the list. Select the button object that you are using that has your script attached to it with the LoadFirstLevel() function in it. Then, select the script itself in the box on the right, and then under that script selection, you function LoadFirstLevel() should appear, so select that. Then, every time that button is clicked, it will call that LoadFirstLevel() function. The LoadFirstLevelFunction might look something like this in your script.

function LoadFirstLevel()
{
Application.LoadLevel("Level Name");
}

be sure to add your first level scene file in the project settings tab in the toolbar so that it can be accessed. I hope this is what you were looking for and good luck