3827892 - How to have additional fields populate based on a selection of a field?

Client would like to explore options to help track their large meeting spend and one of the ideas is to add additional dynamic fields when a user chooses a specific Business Purpose category. So when specific items are selected for this field, they would like additional fields to populate.

Client would like additional field values populate based on the data selected on a field. Conditional fields , KBA , CON-EXP-ADM-FOF , Forms and Fields , CON-EXP-ADM-EXT , Expense Types , Problem