What is UTC to CET/CEST?
Coordinated Universal Time (UTC) is the world's time standard: it never shifts for seasons and every other zone is described as an offset from it. Central European Time (CET/CEST) is the clock used in Germany. Converting UTC to CET/CEST means adding that offset to the UTC reading.
Central European Time is shared by most of continental western Europe, from Spain to Poland, which makes it a common meeting clock for the region.