I am allowed to accompany my LO on her first three day of playgroup. I had sort of brought her to her class a few times before she started school officially. She seemed to be comfortable with the teachers and her classmates but that was probably because I was around. What should I do during these first three day to help her to transit into her school? I am also worried as my LO has not learned to talk.

Slowly ease your presence in classroom (like staying at the back of the class instead of helicoptering around her.) encourage her and talk about her class before and after class. Kids are really adaptable, don't worry too much lest she picks up your stress and anxiety.

Manage your emotions as you don't want to send her the wrong vibes. Keep reassuring her. Do not hesitate to send her to school.

If you are there to observe, encourage your girl to be active in the class activities. i would sit aside to observe.