First, you need to build your menu on your Deliverect account. This article explains the steps that need to be followed to build your menu.
However, Deliveroo requires some extra steps before you can push your menu live. These steps are often overlooked at and as a result, you will not be able to push the menu live. When trying to do so, you receive this notification:

To add a menu description and menu header image, you have to do the following:
Go to the menu section > click edit on your menu

The next screen will appear. It is now time to add a menu description and a menu header image. Only when this is filled in is the menu ready to be pushed.
Please note that without this, your menu can never be pushed live on Deliveroo. It is mandatory for Deliveroo due to their website layout.
Moreover, Deliveroo has also added another requirement allowing you to add allergy and diet tags to your products. Please read the following article on how to manage this.