I just got the Canon R7 and I'm so excited to finally have a real camera! I've been using my phone forever but I wanted something better for my cousins wedding next month. I keep hearing people talk about prime lenses being way better for blurry backgrounds but I honestly have no idea what that even means or which one fits my camera.

I dont want to spend more than like 400 bucks right now since the camera was already expensive. Is there one that's good for people portraits? Sorry if this is a super basic thing to ask I just really dont want to buy the wrong thing and waste money. What prime lens should I actually get?