[subject] + 显得 + [adjective]
[thing] + 让 / 使 + [person] + 显得 + [adjective]
显得 is a verb meaning "to appear, to come across as". It goes before an adjective, usually with 很, 有点儿, 特别 or 更 in front of it, and describes the impression someone or something gives.
The most common 显得 sentence names the cause: a piece of clothing, a colour, something nearby. The cause is the subject, or it comes before 让 or 使.
看起来 is the speaker's guess from what they see: 他看起来很累 means "he seems tired, I think". 显得 reports an impression that is plain to anyone, and it is the one to use with a cause or a comparison. 看起来 can also start a sentence and take a whole clause; 显得 can't.
显得 takes an adjective. To say someone looks like a type of person, use 像.
显得 is more written than 看起来, and it is common in descriptions of people and places.