普 is a bound morpheme that does not stand alone as a word in modern Chinese. You will find it as the first component in many compound words where it carries the meaning of 'general', 'universal', or 'widespread', such as 普通 (common), 普遍 (universal), and 普及 (to popularize). It is also used as a surname (e.g., 普京 Putin). When you see 普, expect it to be attached to another character — use the full compound word, not just 普 by itself.