So to make it work first of all make a github repo and then make a new file called "version.txt" open it and type the version of ur app then use the raw url of the file and put it here in updater.c:
system("powershell Invoke-WebRequest <url> -OutFile C:/Windows/Temp/version.txt");
Then when u wanna update change the version.txt to another version like 1.1.0 that will cause the app to think is outdated Full github repo here https://github.com/shourgamer2/C-Updater-Win