Go with the flow. Do what the children want to do, within reason. Aim to go outside at some point - walk around the area. Depending on the age of the children, they may know the route to their favourite playground. Could go for a outing to see where the school is, where pre-school is, where church hall is or other venue for activities, get a feel for the area.
Go through safety things with the parent(s) such as making sure car seats fit in your car if you are using your car to transport children. Having a key to get in the home and what their usual procedure is for keeping the house secure.
Find out where things are... coats, gloves, hats, boots, waterproofs, school bag, clothing, nappies & associated things, food & cooking utensils, cleaning equipment. How to use the washing machine, dishwasher etc.
Spend time playing with the children to see what they like doing.