To add a field in FluentForms, follow the steps below:

1. In the WordPress dashboard, go to FluentForms.

2. Find the form you want to edit and hover over it and click on "edit".

3. In the left panel of the form editor, find the "fields" section.

4. Click on the field you want to add.

5. Drag the field from the left pane and drop it in the design area of the form.