Campaign Budget Commitment - planned, reserved and committed

Hi Team,

Currently I'm trying out budgeting and have a few questions on campaign budget commitment values.

How these values "planned, reserved and committed" are considered in budgeting?

Also, does these values have any relevance in Budgets we define as in below snapshot?

How is the REAL cost used in campaign budgeting?

Appreciating any pointers to clarify my queries

Thanks