Apple interview

Hi all, I have a 45min interview at Apple for the role RF and FIRMWARE engineering next week(Germany). If anyone has given interview for the same/similar role could you please help me with the process and questions asked. Also I am kinda confused if I need to focus on DSA or my core concepts related to electronics. FYI In the mail they have mentioned that there will be questions related to coding , firmware development, RF & embedded systems, testing frameworks etc.