Would be much easier to advise if we knew your usual habits in detail.
Off the top of my head:
1 Do you meal plan and plan your shopping? People who shop “off the cuff” spend more and have high food waste, only shop once a week and don’t top up! Use EVERYTHING you have in before getting more favourites!
2 Are you brand slaves? An area often explored on “eat well for less” and which Martin Lewis via MSE addressed long before that. His tip which I’ve followed and benefitted from is to gradually move down the brand “levels” so the levels are:
Named brands
Supermarket luxury
Supermarket regular
“Unnamed” brands (the kind of thing you’ll find in home bargains etc they’re branded but not a high end/well known brand)
Supermarket budget range
The idea is you move down a level with each shop until you reach your “nope not worth the saving” limit
Eg
I will not compromise on fairy Liquid original, I’ve tried umpteen others and it’s the only one I think really gets dishes clean and reduces the need for scrubbing!
Breakfast cereal - I’m ok with supermarket regular brand, don’t feel the need to get named but found the budget stuff disgusting!
Dried pasta - Budget! Really don’t notice the difference here at all.
3 are you big meat eaters? Now in all honesty I’m veggie but PURELY from a cost perspective meat is expensive and not necessary every single day. Also consider cheaper cuts of meat and use in slow cooked recipes. Ridiculous to use expensive tender meat cuts in casseroles and curries!
4 are you getting your 5 a day? Which is actually meant to be 9 anyway! Veg is much cheaper than meat and filling. Even the 5 a day option is meant to be 3 veg 2 fruit. Also many people vastly underestimate the size of a veg portion. There’s a reason why “paupers food” is veg heavy, poor folk in days past knew that veg made a meal go further. Also soup as a starter every day fills up your family cheaply & healthily too. Bread on the side helps fill up cheaply too.
On the fruit side
we also eat a lot of fruit like strawberries and grapes as a family.
These are expensive fruits!
Apples, pears, oranges, bananas etc are cheaper, last longer and just as nutritious
Re toddler - Make the “boring” fruit fun by cutting into fun shapes, letting them have it with yogurt as a “dip”, mixing with the berries and grapes so that they go further...
5 Do you cook TOTALLY from scratch? Including sauces? They are very easy to make from scratch once you know how and much cheaper and healthier too