Oh well, you need to explore in the outskirts to find the witch.
You can of course try to decode the directions (or find them on a random event there)
But if you don't feel like doing that, it's North > West > South
She will tell you where to go later, and once you get an item check it on your inventory.
Then you will have a new icon in the map, you can proceed from there.
Oh yeah, after you get some training in you should check Chloe's room in the morning.