This is an example of a fundraiser chart that is embedded into a webpage. You can modify the amounts in the yellow donations section in the Google Sheet below. This in turn will change the total in the green section, which will be reflected in the Embedded Chart below. The general directions for modifying the Display tab URL and embedding the iFrame can be found in the orange section. Feel free to make a copy and check out how it all works.
Have fun, Jeran