Hey guys, i’ve been using an app to learn Korean and it also looks so cute! It's really useful and helps you to learn Korean. Check it out at https://play.google.com/store/apps/details?id=kr.eggbun.eggconvo

In more native way of saying, when we talk about the dream, we tend to mention who or what was appeared in it. So it is like

I had a dream about you. => You appeared in my dream.

너에 대한 꿈을 꿨어. => 내 꿈에 너가 나왔었어.

너에 꿈을 꿨어요

Of course thanks so much

너에 관한 꿈을 꿨어.

Hope it is helpful to you:)