yeap, right. 들어오세요 is same a 들다, '들다'+'오다'. 네, 맞습니다. '들어오세요'는 '들다'와 같은 의미를 가지고 있어요. just have a some more respect to listener. 그저, 조금 더 청자에게 예의를 갖춘 말일 뿐입니다. i think you confuse a 들다 is verb mean it, 아무래도 '들다'의 활용에 대해 헷갈리시는 것 같아서, here is a how to use a 들다. i wish that help your question. '들다'의 의미와 활용형에 대한 정보를 적어드립니다. 도움이 되셨으면 좋겠습니다. 1.(inside from outside) to come in; to get in; to enter 2.(light or water) to come in; to get in; to enter 3.to move to; to get in; to stay 4.to get on; to take (a certain road.) 5.(to a place to sleep) to get into 6.to cost; be spent; be used; be poured; be invested (money, effort, etc.) https://en.wiktionary.org/wiki/%EB%93%A4%EB%8B%A4

들어오세요 can be translated as "Please, come in." To break it down: 들어오다 (verb "come in") + -(으)세요 (verb ending used when you want to tell sb to do something politely aka imperative).

I think there was a little confusion. 듣다 means to listen. When used in present tense, its true that 듣다 becomes 들어요. However, 들다 has many meanings, including to enter / go in / walk in. So in this context, the meaning is 'please come in'. Hope that helps!

The verb stem for "listen" is 듣다, not 들다.

I see that I have a typo and 들어으세요 is 들어오세요. This dialogue is from a lesson about honorifics so I thought 들어오세요 was 들어으세요. Thanks for all the comments.