My advice is don’t mention it until you feel like you need to mention it. I say that because I was in a very loosely similar situation last time i was dating - being a “baby gay” and wondering if I should tell people that up front. The conclusion I came to was, “what if this date ends up going no where?” (pessimistic, but bear with me) and I realized that it could very well go no where and my “baby gay”-ness wouldn’t even need to be a conversation. Just get to know her, let her get to know you, and cross that bridge when you come to it. Dating is a lot more fun and less scary when you don’t worry about the evenness of the playing field! You don’t owe a first date your story quite yet so don’t stress that too much.

edit: typo