I can't get in!!

Hint 1 of 11:

Get the key.

Hint 2 of 11:

The key is in the lock on the inside.

Hint 3 of 11:

Push the key through the lock

Hint 4 of 11:

with the dart.

Hint 5 of 11:

Use a magnet to bring the key to the outside.

Hint 6 of 11:

Make the magnet using the battery,

Hint 7 of 11:

door handle,

Hint 8 of 11:

wire (part of the portrait above the door)

Hint 9 of 11:

and vinegar (outside the lighthouse)

Hint 10 of 11:

Wind the wire around the handle,

Hint 11 of 11:

pour the vinegar in the battery,