May I say "Let's me sanitize your hand with alcohol " As a receptionist, I have to make every visitor sanitize their hands due to 2019ConV. Would you guys tell me How I should say the sentence in a polite way?

What's the differences between these sentences I need you guys tell me about the differences between these three sentences ! SO confusing >< thank you first <3 이렇게 하는 거 어때요? 이렇게 하는 게 어때요? 이렇게 하는 건 어때요

What's the differences I need you guys tell me about the differences between these three sentences ! SO confusing >< thank you first <3 이렇게 하는 거 어때요? 이렇게 하는 게 어때요? 이렇게 하는 건 어때요

컴퓨터 써도 돼요 vs 컴퓨터 쓸 수 있어요 I'm kind of knowing the grammar. 도 돼요 and 수 있어요 means "can do something"... So ,these two sentences are the same? or They have the slightly differences? 좀 도와주세요 :)

What's the differences about 별로 마음에 안 들어요 and 마음에 안 들어요? These two sentences are the same? or They have the slightly differences? 좀 도와주세요 :)

Does this sentence make sense? 這句韓文合理嗎? If I would like to say "Why did you come here so early?" "왜 일찍 왔어? " Does this sentence make sense? 如果想問"你怎麼這麼早來"? 這句韓文合理嗎?

빌려 주다 vs 빌려주다 的例句 Hello 這兩個我懂一個是borrow 一個是lend的概念 借入 借出 但能否提供例句給我呢? 背了好久總是忘記 嗚嗚 Could you plz give me the sentences about two of them? I've been confused by them all the time ><