I think there are two things to learn straight out of the gate...
1) To paraphrase Emeril - those knobs on the stove? They're there for a reason. Never cook on high - or even medium high - unless you have a specific reason for doing so.
2) Taste your food as you go along - and especially towards the end. I can think of multiple occurrences from my experience where someone has placed a dish on the dinner table and said "I hope it tastes good..." Hope is not a good cooking strategy or technique.
Ok, and a bonus one...
Think small. As a learning exercise, boil a small portion of spaghetti. Drain, and over very low (or maybe even no) heat, add a little pat of butter and mix, Taste. Add a little salt and mix. Taste. Add a little pepper and mix Taste.
If at any step it's to much, throw it out and start over. Don't make your failures traumatic. Use them to remember what not to do. Because cooking well is about adjusting.
Edit: Link didn't work. youtube: "Jacques Pepin Recipes"
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