They should! There are lots of ways to learn: e.g. while in a public sector job that takes an active role in the agency’s budget process, by working for an elected official, by volunteering on a government committee or for a non-profit that takes part in a local or state government budget process, or, even by reading and self-study.
For example, there is a “Local Budgeting Manual,” among many other useful training and guidance documents on public websites for anyone who wants to learn about budget timelines, requirements, and laws.
From the Local Budget Law page of the Oregon Department of Revenue: