A dark red long party dress shows a one-sided shoulder line, a high curved front opening and a remaining hem that reaches close to the floor.
The opening reveals part of the leg and pale strapped shoes, while the skirt remains long alongside it. This is a useful starting point for choosing the front view you want. In your own dress, look at an ordinary standing position before stepping forwards. Decide how you would like the opening to look in both positions rather than copying the photographed leg position as the only target.
The picture does not fully answer the rear-view question. Ask another person to observe the back as you step backwards or turn. An open front can be combined with a different length behind. Both observations belong in a fitting without being treated as the same thing.
The pictured heel shape is only one possible combination. Try the actual intended shoes and check the lower edge with that pair. A planned change requires both versions. This pose cannot establish the material, alteration allowance or an option for fastening up the rear area.