Trying to understand firmware for internship?

I was recently hired as a software engineer into a firmware engineering department at a major company as a summer intern. I'm a very inexperienced intern (entering junior year of college) and have found literally everything they're doing super confusing. I'm not even sure what questions to ask. How can I better understand firmware, testing in C, embedded systems, etc? I'm so far feeling very uncomfortable and am seeking information from experienced people who may have gone through a similar situation. The issue is there is very little help, guidance or mentorship at all so far from my team and it's a little disconcerting. Thanks.