Chemotherapy Questions?

Hi there! I hope it isn’t offensive to anyone that I’m here asking questions. I’m a writer and I’m trying to do some research on breast cancer, but I’m confused on a couple of points. I can’t seem to find the answers, and I’d be very grateful for any help. I do understand that it varies, depending on the individual, the type of cancer, etc, but I’m looking more for estimates. What's the usual, if there is one.

The breastcancer.org website says you receive one cycle a number of days a week, with a certain number of “off” days, and that the entire cycle would run 3-6 months.

1: How often would you receive a cycle? For example, would you have more than one cycle a year?

2: How many years would you have them for? Is there a limit to the number of years?

3: when do you stop having them? do you just go until the cancer is gone? What happens if it just keeps coming back?

Thank you very for your time!!