Does the IPO (Input-Process-Output) model cover everything in software logic?

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Hi everyone! I’m currently working on a Banking System project in Python. While building it, I realized that I can break down every single feature (like Login, Withdrawal, or Deposit) into three distinct stages:

INPUT: Getting data from the user.

PROCESS: Calculating or validating that data.

OUTPUT: Displaying the result or a message.

My questions for the community are:

• Is this IPO model the true foundation of all programming, regardless of project size?

• Is it 'safe' to rely on this mindset for my entire learning journey and coding life ?

I’d love to hear if there are other professional frameworks I should keep in mind as I grow. Thanks!"