If you want to change the font, style and text size for an object, you can do this by selecting the object and choosing your font/style/size from the Formatting options within the Home tab.

You can also lock this formatting style by using the ‘Lock Text Format’ button. Once you have locked your text format, this can be applied to other object/s by simply selecting the objects you wish to format the text for and clicking the ‘Apply Text Format’ button.