This is a basic train station with not much to offer except providing the service of being a train…read morestation. There's a Relay type of convenience shop inside and a coffee vending machine. Both seating areas have several power outlets, which is convenient. To use the WC, you need to pay €0.30. It's free to use the one on the train. If you want real food that is grab and go, the nearest is a boulangerie with sandwiches, baguettes, etc. Walk away from the station, walk to the left one block, then turn right and walk one block. Before you reach the end, you'll see the blue canopy shop.
This is the train station stop for Monet's Giverny home and garden. So it has a regular rush of train riders including the locals. Too bad there isn't more at the station itself while you wait for the train. No comment on the staff as I already bought my ticket in Paris so no interactions.