Welcome @hayatoryoko, to the community!
Your screenshots only show folders with bare IOC files. However, these only contain a description of how to configure the peripherals and pins of the respective STM32. To get a C programme, you must first open this IOC (starts the integrated STM32CubeMX tool) and from there generate the actual project with Project > Generate code, in which you will then also find the main.c.
BTW: I recommend using the latest version of STM32CubeIDE, as your screenshots still show the workspace of the old version 1.13.2. I also recommend studying UM2553 (Quick Start Guide) and UM2609 (STM32CubeIDE user guide).
Hope that helps?
Regards
/Peter
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