Your question is Evaluate Model Overfitting. Take a moment with it on the right.
Talk me through your thinking if you like. When you're confident, submit your answer and I'll grade it like a real screen (7/10 or better passes).
You've trained a model that looks very strong on the training set, but the team is worried it may not generalize well to new data. You want a clear way to tell whether the model is memorizing patterns instead of learning signal.
How would you evaluate whether a model is overfitting?