I don't understand how 仕掛け is used in on the second panel:
仕掛けはもう竿に付いてるから
針にエサつけて放りこみゃいい
My attempt at understanding this:
Because 仕掛け is already attached to the rod, (you just need to) attach the bait to the hook then cast.
I would think 仕掛け = gadget = hook, though 針 is used to refer to hook right afterward, so I'm a bit doubtful that's it.