영화 볼래요? ( Will you watch the/a movie?)
영화 볼까요? (Shall we watch the/a movie?)
정은 씨, 같이 식당에 갈래요? (Jung-eun, will you go dine with me?)
정은 씨, 같이 식당에 갈까요? (Jung-eun, shall we go dine together?)
정은 씨, 이번 연휴에 같이 여행갈래요? (Jung-eun, will you go travelling with me this coming holiday?)
정은 씨, 이번 연휴에 같이 여행갈까요? (Jung-eun, shall we go travelling together this coming holiday?)
Hope you find this helpful. Note how the subject of each question changes by having either -래요 or -까요 at the end.
* Please also bear in mind that --ㄹ까요 question structure also has other functionalities other than the one mentioned above, and is not thereby limited in its usage as such.