Most of this look is created in-camera rather than as a Lightroom-only effect. It comes from shooting during golden hour, placing the light source behind or toward the side of the subject, and often shooting somewhat into the sun for a warm, soft backlit glow. The floating bright spots can simply be particles or seeds catching the light.

In Lightroom, you can push an image in that direction:

• Warm the white balance.
• Use Split Toning / Color Grading: add a golden tone to highlights and a cooler grey-blue tone to shadows, then adjust balance toward the highlights.
• Add a radial filter where the light source would be, invert it, slightly raise exposure, and warm the temperature to create a subtle glow.

This can make the effect more believable, but it won’t fully replace the quality of actual sunset backlight. For best results, capture the lighting at golden hour first, then use Lightroom to enhance it.