Just say "Hey Google, order food from [name of restaurant]".
If you're looking for somewhere to deliver food to your door, Maps or Search are probably going to be your first port of call. Depending on the service, you can even complete your purchase using Google Pay, which would result in a completely seamless transaction.
When you use Google Search or Google Maps to find a restaurant, you will now see a button that says, "Order Online".
Google Search, Google Assistant, and Google Maps all now let you order food delivery from some of the biggest food delivery services. It then just takes a few more clicks or taps to choose what you want from the menu, and specify a delivery or pickup time to suit you. After the payment is accepted, you can simply wait for dinner to be delivered, or if in your vehicle, pick it up on the way home. When you utter those words to your Google Home speaker or smartphone, the Google Assistant will cheerily launch into a short story most often meant to help young kids with ... Assistant can pull up your previous orders from that restaurant, and you'll be able to select one of your favorite combos quickly. There's no need to even pick up your phone, because re-ordering can be entirely voice-controlled.
The entire ordering experience is done through any of the three Google services. The interface is now active with restaurants supporting ChowNow, Delivery.com, DoorDash, Postmates, and Slice.