There is an old saying that 'if you fail to plan, you plan to fail'.
A budget is a personal financial plan that you can use to make sure you have plenty of pay left at the end of the month. Learning to make, plan and run your own Budget is a skill that takes time to perfect.
The Benefits of Budgeting
You take control of your money
Avoid unnecessary debt
Pay off debt faster
Show banks you are a low credit risk
Much better for your mental health
You become a better lover (I might have made this one up)