All changes are different. Some are instantaneous while others take decades. Some can successfully be instant and spontaneous and others must be carefully planned.
Any career change for me will definitely take a long time. Hopefully not decades though. In this case I want the change to be instant and it is possible that it be but I don’t see the change being easy and/or successful without taking the extra time to carefully plan.
Time to carefully plan.
How does one become a successful calligrapher?
Step 1: Learn the craft. Practice, take a class, practice, research the topic and others in the field, practice.
Step 2: Gather together a portfolio
Step 3: Join a professional organization to meet contacts, learn, get insurance, etc.
Step 4: Either get employment in the field or become an entrepreneur.
Step 5: Continue education.