If your daughter is in Year 10, and I assume a summer born baby, then she can't be far off 15, considering we're in June. My son is in Year 10, but an Autumn baby, so is 16 coming up.
I understand that you don't want your daughter having intense relationships that might distract her from her studies. However, putting in a complete ban, will simply make her lie to you, sneak around and hide her boyfriend. At the moment she trusted you enough to tell you, and that's a trust you don't want to lose.
There's nothing wrong in your daughter going to McDonalds, cinema, bowling etc with this boy. It's perfectly normal for a girl at very nearly 15, to be interested in romantic relationships.
Yes, you need a conversation regarding contraception, consent, healthy relationships and the importance of maintaining her friendships with friends.
I didn't have my first boyfriend until I was 17, I was shy, and rather awkward teenager. However, my Dad was very overprotective, didn't want any boy anywhere near me, treated me like I was still 11 when I was 17. It was awful. My Mum was much better, and she'd regularly have to tell my Dad, that I was 17, not 12 and he needed to accept I was growing up.
Instead of having a blanket ban, put in boundaries and parent the situation.