I see that you are thinking about being a doctor for your career! Really cool! I'm proud of you for thinking ahead to the obstacles you might face.
Currently, general practitioners in the US are about 50/50* with respect to men and women. That gender ratio is less equal when you examine doctors with specialities. When gender ratios are not equal, that does mean that there are biases that folks will need to face to navigate their profession.
I think, at first, it's going to be difficult in the ways that is difficult for everyone. You'll have to take some tough math classes. You'll have to take some tough science classes, like Physiology and Anatomy. But every once in a while, something dark will happen that will take you by surprise. A older professor might say something like, "Why are you working so hard? Why not just get married?" Another student will say to you, "You just got in this school because you are a girl." I give these particular examples because they are things that actually happened to me while getting my PhD in STEM.
As you make advances in your career, there will be more little things like this that take you by surprise. I can't guess what they will be, because I'm not a medical doctor, but looking at the gender ratios in some specialties, I can't say there will be none.
But you will learn to navigate these obstacles. You will find a group of friends and colleagues that take you to ice cream when something terrible happens. You will finish the class from that awful professor and try never to take another class from them. You will learn amazing things and have a great impact on your patients.
But I can't lie. There are gonna be moments of yucky bias.
I wish you all the luck in the world.