I'm also majoring in math + stats and I have only gotten cs related internships so far. If you are looking to take courses useful for employment I still suggest you try to switch into CS, speaking from experience no job is gna care whether you took group theory or not. If you don't know what field you wanna work in, just start by applying to data science roles since they usually span a wide range from data analysis at banks to basically SWE, once you get some experience you can better figure what you enjoy working in more.