Creating the custom fields
First, start with laying the foundation of your Flexible Content by creating the Custom Fields that you need in your project.
Search for Custom Fields in your menu panel
Click Add New
Give your Field Group a relevant name.
Click on the + Add new button and add the Flexible Content field.
Define your Flexible Content Layout
Add the fields you want to use in your layout. Go to support fields to check out which ACF Fields Rexy supports.
After adding all the layouts and defining the location you can hit publish.