The Selected Columns panel
In Select Data Fields (step 3 of the wizard), everything you tick lands in the Selected Columns panel on the right. A chip shows the running total (17 selected). The first entries are key columns that every view of this type carries - Case ID, Site ID and Site Name for a case view - and they cannot be removed.
Below them your own picks appear in the order you ticked them, each with a drag handle ⠿ and an ×. You can reorder or remove here, or wait for the next step. Untick a box in the middle panel and the column disappears from the list.
The number badges on the module list at the left tell you how many fields you have taken from each module - useful when a view has grown long.