I really want to understand the topics for mechanical engineering, BUT I do not know what I need to learn or what to start with I'm kind of lost... I want to feel like I really understand the topics but what is it that I need to learn and how?

PLEASE , if you are experienced in mechanical engineering - I BEG of you tell me what I need to learn and where to start, what apps, you tube videos ANYTHING! just need to be (free...)

hi i have a robotics engineering technical interview coming up. i wasn't really given any specific details, just that the interview was technical. is there is anything i should look out for or prepare for in advance?