Q.Cabbage
Are the huge leaves growing where I planted cabbage, my actual cabbage?

Certified GKH Gardening Expert
This is part of the cabbage plant, yes. What most people consider to be "cabbage" would be the tightly formed center mass of leaves that form much later. Your plant is still young, and has not had time to form fully yet. If has been too long, then you might consider if the plant is getting enough light. They are full sun, and will prefer to be in bright sunlight all day. Here is an article that will help: https://www.gardeningknowhow.com/edible/vegetables/cabbage/growing-cabbage.htm