Every new role will give you the opportunity to learn new skills and overcome challenges you haven't faced before. Whether you are applying for a customer-facing role, accounting or a software engineering role, identify a couple of responsibilities where you anticipate a little bit of a learning curve. It's okay to not know everything! It's also better for you to admit it from the beginning than to come of up with some sort of vague statement to try to prove you are experienced in something you are not. Interviewers will see right through it! Be honest about the challenges and be brave enough to ask questions. Do a little research before the interview on any task, software or system you are unfamiliar with.