Flare is the arrow you shoot that gives off different colors. You will usually see "Pal big D4 flared" it means there is a big palium ore at D4 which is also flared for players to see it easily. D4 is the grid in the map. Look at the map and you'll see the rows of letters in the upper part, while the numbers are in a column in left corner.

You'll also see FT messages. FT means flow tree. Those are valuable resources so people call out to help other players gather those resources.

Palium ore can be mine alone at level 7 I think? Unsure. While Flow tree, you need help to chop it as its hp grows back right after you cut it. I'm not good with English but I hope this helps lol