To replace placeholder text on a slide, you double-click the text and type your own. If you want to add other text to the slide, apart from one of the existing placeholders, you add a new text box then replace its placeholder text.
The text box itself is an object that can be modified like most other objects; you can rotate it, change its border, fill it with a color, layer it, and more. There are text-specific controls for changing the appearance of text within the box—including its font, color, size, and alignment.
You can also add and edit text in a shape or table cell and format it like any other text.
Click Text 
in the toolbar.
A text box is added to your slide (you can change how the text looks later).
Type your own text to replace the placeholder text.
Resize the text box, if necessary, by selecting it and dragging any selection handle (white square).
Drag the text box to where you want it on the slide.
To delete a text box, select it, then press Delete.
You can insert special characters in text, such as mathematical symbols; letters with accent marks; arrows and emoticons; Japanese, Chinese, and Korean characters; and more.
Click in the text where you want the character or symbol to appear.
Choose Edit > Special Characters (from the Edit menu at the top of your computer screen) to open the Characters window.
Click an icon at the bottom of the Characters window to choose a category of characters (click the left or right arrows to see more categories).
Click the character you want to insert in your text.
For information about using keyboards and input methods for other languages, go to Help > Help Center and search for “input menu.”