Is this coat warm enough for winter?

No. It is a single-layer polyester overcoat with no lining or insulation, so it works as a spring or fall layer. In cold weather you would need a sweater underneath or a heavier coat.

What is the fit like?

The drop shoulder and regular length give a relaxed, slightly oversized shape. If you want a closer fit, consider sizing down; if you plan to layer thick knits, take your usual size.

How should I care for the polyester fabric?

Polyester usually washes well on a cool, gentle cycle and dries quickly. Avoid high heat, which can shrink or distort the fabric, and hang it to dry to keep the shape.

Does it have a lining?

The listed composition is 100% polyester with no lining mentioned. Expect a single-layer shell, which is lighter but less smooth against the skin than a lined coat.