There are opportunities in baking to deviate from the recipe, but it's important to know how the ingredients react with each other during the mixing or baking process. I know some people who add an extra egg to their batch of cookies, some who add extra butter, etc and those who follow it verbatim. There's certainly a lot less room for error, and a lot of small mistakes that can absolutely fuck the outcome, but there is room for creativity if you know which components are critical and which are optional. (and for which recipe, because some are more sensitive than others)

Just don't mix up baking powder and baking soda like I did when I was 11. Worst mistake of my life, that batch of waffles was completely inedible and had to be tossed 🙁 (idk if that counts as baking or cooking but whatever)

Recipes might say to weigh the flour or at least scoop and scrape so the cup is level but it really doesn't need to be that precise. I don't even use measuring spoons for exact measurements of baking powder. I just scoop what looks like half a teaspoon using an actual teaspoon, not a measuring teaspoon.

Now if it says 500 grams of flour and you use 1kg, it's going to be a problem. But +/- 10% isn't noticable.