Yes! I would say don’t try and suggest any tips or improvements, don’t try and fix her stutter, but absolutely learn more about it, her experience with it, how she would like you to support her. You could approach it like “It’s been so wonderful getting closer to you, I’m so lucky to be your boyfriend - one thing that’s kinda intimate that we’ve never talked about is stuttering. Do you think you’d feel comfortable talking about stuttering to me? I know it’s part of your life and I want to understand more about it.”