Is this jacket warm enough for winter?

It is a down-filled quilted jacket, so it handles cold dry days well, especially layered over a sweater. It is not a waterproof or hooded shell, so it is less suited to heavy rain or exposed wind.

No. The design is a collared zip-front jacket with elastic trims at the cuffs and hem, so a hat or scarf is needed in wet or windy weather.

How should I wash a down jacket like this?

Use a down-specific detergent on a gentle cycle, then tumble dry low with dryer balls to break up clumps. Avoid fabric softener, which coats the feathers and reduces loft.

Is the shiny finish a coated fabric?

The shell has a glossy treatment that gives the sheen. Wipe light marks with a damp cloth rather than scrubbing, since the finish can dull with harsh cleaners.

How does it compare with a matte puffer?

Same warmth principle, different look. The glossy shell is more of a style piece, while matte technical puffers usually add water resistance and a hood.