Changing careers at 12 years into a job, is it realistic? after 12 years as a bank teller

After 12 years as a bank teller I am thinking about moving into a different field. I worked as a bank teller before this. I have good customer skills and I am comfortable with spreadsheets. Has anyone made a similar move?

I began with informational chats, then a short online course, then a related entry-level role. It took about 8 months.

Keep everything in writing and save the confirmation numbers. It saved me later.