The answer to 'how to maintain countertop' is to clean and seal the surface regularly. Wipe up spills immediately, use a mild detergent and soft cloth to clean daily, and apply a countertop sealant every 6-12 months to protect against stains and damage.
Avoid using harsh chemicals, abrasive scouring pads, or cutting directly on the surface, as these can scratch or etch the material. If you notice cracks, chips, or other damage, it's best to have a professional inspect and repair the countertop.