처럼

like, resembling

Goes on a noun to compare something to it: 강아지처럼 귀엽게 is "cute like a puppy", 코미디언처럼 재미있으세요 is "funny like a comedian", 옛날처럼 is "the way we used to". It always attaches directly to the noun with no space, so the comparison hides inside a single word. 같이 means much the same thing and is interchangeable in most sentences; 처럼 is the safer choice for beginners because 같이 also means "together" and can be read the wrong way.