Reading slang from a stranger
Most chat slang is harmless shorthand typed fast. A decoded message usually just means someone is friendly and in a hurry. Two things are worth a second look: questions about where you are or who you are (ASL, wya, IRL questions), and requests to move somewhere else (dm me, add me, hmu). You never have to answer those.
For the meaning behind the meaning, like whether “idc” is relaxed or cold and how to reply to “wyd”, see the chat slang dictionary.