I think its automatic, you dont need to equip then. if its dark there, then you still need to do stuff before you go there.
its still dark even if I have the lantern.
Did you already catch a firefly to put inside the lantern with the Bug net that you get from giving a rune to the Rune Guy?
yes I did
In last case, there is another route you can take to avoid going to the forest, but at this point , you better off checking a walkthrough.