Kids that straight up ignore you?

What do you do when substituting when kids just straight up ignore you? Like when you tell them to go sit in their seats, they stay standing chatting with their friends or running around the room screaming. Or if they see their friend they go running out of the room.

One school I've been subbing at, is in general chaotic with many students with behavioural issues and the students seem to do whatever they want. This school also does not give subs access to the IEP's and I have yet to be given an actual safety plan for the students. This one class is a 6/7 but it's a pattern I see across the school. They also refuse to do any of their work and when their teacher comes back, there isn't any consequences. One student even said to me "it's not like anything is going to happen."

But they do seem to respect their teachers to a degree but I often still see them in the hallway doing whatever they want (especially during lunch- lunch duty is a mess in the intermediate hall)

TLDR: What do you do when a good chunk of the class ignores you and misbehaves (running around the room, throwing things, breaking rulers etc). The teacher in this particular room has no reward system and we can not take away recess as subs.

This seems to be an issue I only encounter at this specific school. I'm still a new teacher so my classroom management isn't perfect but I often accept intermediate grades at other schools and have been just fine.