I'm very new to XCode. My compiler will only run the first file that I have created, even if I select the other ones. Please help!!

I'm a university student and this is my first time coding anything. I was doing pretty good but now, for some reason, my xcode will only run the first .c file i made within the project, even if i have a different one selected. My screen is shown in this screenshot to make it make more sense.

https://imgur.com/a/yjNi9QA

The "Hello world" code is in the first "main.c" file on the left, but whenever i try to run q1d or q2a, it only runs Hello World, not the actual files. Please help!!!!

You do not compile file by file. You compile the whole project, starting at main.

I'm very new to XCode. My compiler will only run the first file that I have created, even if I select the other ones. Please help!!
 
 
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