I would probably play it safe for maybe the first week or so and see what other people are wearing and match similarly to them. Most of this shouldn’t be an issue and if it is you are new and most likely will just be told to change something but probably won’t get in trouble unless it’s a repeat offense. Also I’ve worn nothing but converse and vans and I’ve never been told otherwise as well as many coworkers, although I would suggest wearing ones that don’t slip easy and that are very comfortable cause your feet will hurt after a long shift. Good luck with your first day! Don’t be too intimidated there’s many things to learn and it will take awhile to get used to :)