Unfortunately, Calibri program doesn't have a function that can create figures based on an exponential function. However, there are plenty of tools that you can use in order to accomplish your project. To create a curved line, you need to hold down the left mouse button while hovering over the available tools from the main window of the program. The curved line is under the third tool (by default, this tool is the line). To learn more about the available tools, I suggest checking the Help menu. There you can find an User Manual in which all of the program's functions are explained.