If I want to create a reminder notepad, when I press the Checkbox on the second page, the pie chart on the third page will change, and there are currently 3 Checkboxes. When you press 0 Checkboxes, the pie chart will show 0%. Each time you press a Checkbox, the value of the pie chart will increase until it reaches 100%. How to write a program?
Hello @yunx900102fvsv, welcome to Thunkable! 
You can find more information on how to create charts in our docs: Charting in Thunkable | Thunkable Docs
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