I noticed that when I copy and paste a title card. When I make a change in the duplicate, it changed the original title card that I copied from? Why does that happened? Is there a way to change the setting that when I make a copy and change the copy of the title card, it doesn't affect the original card?

When you paste, you should be presented with a dialog that asks if you want to Create a New Copy or Create a Reference to the Original Media.

Choose "New Copy" and it will be editable independently of the original.

Gotcha, thanks Seth!

It also leaves the original selected until you select the new one.