Suggestion required..

Hey, I have 3 years of experience in building gen ai and agentic ai based applications. I have used RAG, LLM, Multi agent orchestration etc. Currently I am trying to switch and appeared in three interviews, in each interview I noticed a pattern, after the topic I mentioned above they asked questions from ML and the data science part, like bagging and boosting and forecasting system design etc. I have no hands on experience in this. I am studying regression, random forest etc algos. But questions are not coming directly from these areas. Can anyone please suggest which topics I should focus on to crack the interviews.