Advice for switching schools my junior year?

So i moved in with my dad this summer and im switching my high school going into junior year. I only know one person at this school and im kinda freaked cause its boca so its very cliquey. im not a shy person but i feel like im going to be very flustered with the whole day so any advice? also this is going to sound stupid but i dont want to sit alone at lunch how to find someone to sit with without sounding pushy?