Another example of the internet age and computers vs learning stuff at school that is actually useful. When I was at school (centuries ago) we had proper cookery lessons every week. We would take all the ingredients for a dish, prepare and cook it - boys and girls. Nowadays the emphasis seems to be on tech which is great to look for info but not so great if you're hungry.
People should really prioritise what is important in their lives. I often hear people moaning that they have no money but spend a fortune on mobile phones and the internet etc. You will probably argue that your NEED the internet to live but food is far more necessary.
Jamie Oliver did a £1 a portion series of recipes, available on line. When you go shopping take a list and stick to it. It is easy to get side tracked into buying stuff you don't need. Before you go, plan ahead and try to get a balance so you're not having the same sort of thing everyday. Pasta everyday for a week is a bit boring. Steer clear of ready meals as they are expensive for what they are, you are paying someone to make them for you, and they are over processed, so full of salt and other undesireables.
Frozen peas and beans are good value as you don't pay for the pods, they are frozen quickly so keep their nutrients and you only need to cook the amount you need. I often add frozen peas or broad beans to dishes as they bulk them up without adding too much to the cost.
With batch cooking eg stews, curries etc you can freeze portions easily in either plastic bags, there are loads of different ones in all supermarkets or for a more sustainable option use the click-lock type of containers (systema is the best because it is affordable but doesn't have the transferable nasties that some plastics do).
Don't buy named brands but instead use supermarket own brands, if you already do this try a cheaper supermarket. I always make a bee-line for the reduced and short dated sections wherever I shop. Dented tins are great because the contents are fine and the tin will be crushed for recycling anyway.
Stir frying is easy, favourite veg and protein of choice (I'm vegan so I use tofu). Dust the protein in flour, which you can season with (sea) salt and pepper (black is best) then fry in hot oil, you don't need a wok, a deepish saucepan will do, when browned I remove and then do the veg. Start with what takes longest eg onions, then peppers, courgettes, broccoli etc and add a sachet of your favourite stir fry sauce (very cheap and less hassle than making one). Put the protein back in to heat and serve with rice, instructions are always on packet. Tip for the veg, cut into similar sized pieces so they cook more evenly. This you can batch make and freeze but it is better to cook the rice fresh each time.
When you have made a few easy options you will become more confident and start experimenting with different ingredients. This is how all recipes evolved. Chicken Tikka Masala happened by accident in a curry house in Birmingham when a customer ordered a curry and I think they said it was too dry, so the owner added a tin of tomato soup, it was enjoyed by all who had it and hey presto a truly British curry was born. Puff pastry happened because the cook forgot to add the butter or and so added it after when rolling out the dough. When cooked, the butter left little air holes in the pastry thus creating flakey/puff pastry.
Don't be afraid to have a go. There are bound to be some simple ideas on line which you can then adapt as you get more confident. If you have never been taught something you can't be expected to magically know how to do it. You are not the only person who can't (or thinks they can't) cook, so get in the kitchen and rattle those pots and pans because you don't know what you can do till you try.