Can I eat from a restaurant which serves pork but also serves halal chicken? Or can I eat veg from such a restaurant and what measures do I have to take before eating, do I have to check the kitchen to see if any cross contamination happens?

1- It’s permissible to eat the halal food from this restaurant.

2- You don’t have to investigate how the food is handled in the kitchen, but if you are confident the halal food is being made najes by the haram food then you need to ask and verify.