Remember to declinate it and write it with „ł”. So it would be „pudła”.

Not exactly. It's maybe not totally impossible here, but it's better to keep to the distinction. You can read more about it here: https://www.duolingo.com/comment/16003748/Difference-between-wk%C5%82ada%C4%87-and-k%C5%82a%C5%9B%C4%87