Most food does not go off because it was old. It goes off because it was in the wrong place, or in the right place where nobody could see it. Storage is the cheapest thing you can fix in a kitchen.
What does not belong in the fridge
Potatoes, onions, garlic, tomatoes, bananas, bread and unripe fruit are all worse for being chilled. Tomatoes lose their flavour, potatoes turn sweet and gritty, bread goes stale faster than at room temperature. Keep onions and potatoes apart, and both in the dark. Stored together they make each other sprout.
Herbs and greens want water or air, not a sealed bag
Soft herbs — parsley, coriander, basil — last a week or more standing in a glass of water like flowers. Basil prefers the counter; the rest are happy in the fridge with a loose bag over the top. Salad leaves rot in their own moisture. Put a dry piece of kitchen paper in the box to absorb it and they last several days longer.
Leftovers go in something you can see through, at eye level
An opaque container on a low shelf is a container that gets found next week. Clear boxes at eye level get eaten. Cool leftovers quickly, cover them, and put them in front of what is already there. Most leftovers are wasted through invisibility, not spoilage.
Run the fridge front to back, oldest at the front
Every time you put shopping away, move what is already there to the front and the new things behind. It takes an extra minute and it is the single habit that removes most forgotten food. Keep one shelf as the eat-me-first shelf. Anything close to its date goes there and gets used.
Right place, visible, oldest in front. That is most of food storage, and it costs nothing but the minute you spend unpacking the shopping properly.