Short answer
Invoice workflows can start from email or forms, then validate data, notify people and archive documents.
How to approach it
Start with a process that repeats often, has a clear output and carries a measurable manual cost.
- write down input and output
- mark decisions and exceptions
- assess sensitive data
- decide who maintains the flow after launch
What to do next
If the process is repeatable and rule-based, prepare a small test scope instead of designing a large system immediately.