How do I make all text with same size, font etc?

How can I make all upcoming text objects with the same font, size, color and all centered?

Any help?

Your question isn't clear. If you want to avoid discrepancies between browsers, you can use SpiteFonts.

I mean: I create one text object and set its size, font etc. Then, how to make it, so that when I add a new text object, it has all values of the first text object?

By placing the first instance of an object in the layout editor and setting its properties in the properties bar, you are setting the default values for whenever that object is created by the system create object action.