As soon as you start editing the code, you have no idea how to start. This phenomenon shows that you did not follow the sample code and understand it while typing the code, and you lack practical programming thinking. It is recommended that when learning programming code in the future, remember to follow the example code, so that you can build your programming thinking (mainly formed by long-term practice), and you can also store the memory of this knowledge, so that your understanding will be deeper. It’s not like your situation, where you have theory but no substantive ability