What prime lens should I get for street photography on my new L-mount camera? I just got the camera and Im so excited to finally start taking pictures but honestly all the numbers like 35mm and 50mm are really confusing me and I have no idea what they actually mean in real life.

Im going on a big trip to Tokyo in three weeks and I really want to take cool photos of the crowds and the neon lights at night but my budget is only about 600 dollars. Is there a specific one thats easy for a total beginner to use? Sorry if this is a super basic question I just dont want to buy the wrong thing and regret it...