Graph Builder

[#1]

Hello,

I have created graphs for 4 sites

, but I would like to set the format for 1 / 2 / 3 / 4 and didn't find it.

where I can change it?

[#2]

Graph Builder uses the format that is specified for the column in the data table.

The Value Labels column property can also be set and Graph Builder will also honor those values.

[#3]

another way to change the displayed text is via Configure Labels:

On the other hand, if you want to change the font format, you have to change the font settings in the preferences - or vote for:
Right-click to change Group font and font size 

If it's just about resizing the text (make it larger for a presentation - or very small to save some space for the graph), you could use the shortcut icon from Graph Builder Toolbar