Night out as anxious mum

Hello mums! Basically i have never been on a night out before. Now my son started school and the mums of his class want to all meet up for a night out for drinks to get to know each other and just meet. I really want to go but im not confident at all. Also i dont drink alcohol so what can i order? What do i wear? Do people walk in alone then find whoever they will chill with or do they walk in in groups? I just have a thought everyone will be looking at me. Help tips and everything pls❤️❤️