Changing careers at 17 years into a job, is it realistic? - any advice?

I want to move from marketing coordinator to something with more stability. I have a little time and a small budget for training.

You likely have more transferable skills than you think. Write down what you did, not what the job title said.

I began with informational chats, then a short online course, then a related entry-level role. It took about 4 months.