For me personally as a home cook I do best when I learn some of the concepts and then I can use whatever I have instead of trying to get a bunch of specific ingredients.
For example one of my staples is braised chicken and vegetables. I know I can use any of certain vegetables I might have (mushrooms, onions, celery, carrots, broccoli, cauliflower, kale, brussel sprouts, potatoes or sweet potatoes, shallots, etc), any of a couple liquids (water, chicken or vegetable stock, red or white wine, beer, etc) and spice it up with (heavy cream, fresh or dried herbs, mustard, garlic, pepper, bacon, butter, lemon, etc). And I know roughly how I want to cook it: flour the chicken and cook until brown and crispy in a pan, take it out and brown any firmer vegetables, add some spices, add the rest of the vegetables and my cooking liquid and bring to a small boil, put everything in a big oven dish, pop the chicken on top, bake at around 400 for 30-50 minutes until the chicken seems done, add any last things that might burn like cream in the final 5 minutes and then plate up and eat.
Now I don't have to go to the store and look for anything, don't have to worry too much about measuring ingredients, don't have to worry about cook time or technique. I can whip up a big family dinner pretty quickly with whatever I have on hand and experiment a bit with different flavors with confidence that it will turn out good.