The only place to find a real definition of the word “normal” is in the dictionary. This word has a place in science but not necessarily in society.
The Merriam-Webster dictionary defines normal, in part, as “approximating the statistical average or norm.” There is no one definition of how to act normally because it can differ vastly from one person to the next.
If you're always trying to conform, you will fail more than you succeed. It is like a gnat flying around in the summer heat; you can see it and try to catch it, but it will keep moving while you become frustrated.
Being normal is a concept that could reduce some stressors in your life, but it can also be triggering. Take this advice with a grain of salt and a lot of grace.