How will i add an option under customizer the event calendar section?

While in the Customizer preview, right-click on The Events Calendar section and inspect it, you’ll get it’s id.
As an example, if you right click on Site Identity section and inspect it, you’ll have at the beginning the following :

<li id="accordion-section-title_tagline"...

So, the id IS ONLY title_tagline
Hope this helps