I agree with Ciana996. Try out talktomeinkorean.com ..it's a good starting point, if you want to learn Korean properly. In order to be able to have a proper conversation with native speakers, you're going to need to learn Hangul, because natives hardly spell words using romanization. Plus, there can be inconsistencies with romanizing. The next important thing to learn is grammar. The usual sentence structure in Korean is subject-object-verb :).
Just to help you out, I'll correct the list of words you put up for future reference! I'll also add the more common way to romanize the words in brackets~ ^^
안녕하세요 [formal]/안녕 [informal] (annyeonghaseyo/annyeong) = hello
잘 지냈어요? [formal] (jal jinaesseoyo?) = how are you? (I think this is better translated as "have you been well?" because most of the time people will answer you with a "yes"/"no" rather than saying how they are lol. Just telling you this, so you won't be confused when you're talking to Koreans)
또 봐요 [formal] (ddo bwayo) = see you later
잘 가요 [formal] (jal gayo) = goodbye
하지마 [informal] (hajima) = stop it/don't do this/that/it etc. (하지만 (hajiman) means "but"/"however")
사랑해 [informal] (saranghae) = I love you
죽고 싶어요 [formal] (jukgo sipeoyo/jookgo sipeoyo) = I want to die
죽을래? [informal] (jugeullae?/joogeullae?) = You wanna die?/Do you want me to kill you?