Look, you need to create input and output pins, create scheme, using "and" and "not" operators. Then, if you finished, press "create" button on top left corner, name this chip and set a color. New chip will appear in bottom left corner.You can use it like that operators aforesaid. Good luck.
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To create a chip with inputs and outputs you need to place inputs, outputs, operators and connect them on screen. "Create" button will erase the screen and make short version of it to small chip box. If you press "Create" when your screen is empty, you will get an empty chip without any functional. I hope, that i explained a thing. Good luck.