okay so here's what i do. i talk. lemme explain:
1: im comfortable with sharing things about my life, but i dont get too personal.
2: when im in a new place, for example, a new school, i talk, because i learned that if you talk on the first day, you have a better chace at making new friends. when i started middle school, i had 5 new friends in the first day.
3: when you start a topic, dont go like "hi im [insert name], what's your name?", no, for me in my opinion, that's werid. i would start on a silly topic or just go ahead and say "uh hey you there, yes you. since im new here and i anit got no friends, lol, imma ask ya random questions and just hope to start a conversation".
4: if the teacher does one of these group activities, which they almost naver do at this point, and they MAKE you ask questions, ask normal questions like "how's the summer break" and stuff then throw in a funny one like "do you play mincraft and have you found dimonds yet?" or just something like that.
5: be yourself. dont try and be like someone else. just, go with the flow. ignore what others say about you.