Healthy budget friendly dinner ideas?

Pasta bolognaise. You can add lots of vegetables and lentils to make it more filling, do a large amount in one go and freeze the leftovers (of the bolognaise not the pasta).

For LO you can either seperate off some bolognaise before adding stock/salt during cooking or you make the whole thing salt free and then add it to taste as you plate up.

I plan each week in advance, wrote a list and stick to it rigidly. We top up on bread, milk and bananas.
Recently we've been eating more potatoes, cheaper than pasta or rice and filling. We buy the large bags of veg (so when planning each week I also look to see what is left from the previous week) and also get the "wonky" carrots and potatoes, the "savers" green beans etc. We have something vegetarian a few times a week as it saves so much money - beans, lentils and chickpeas are really good with a few spices.
My son has pretty much the same thing for lunch each day - sandwich with fresh fruit and some baby crisps. I see a lot of posts on here asking for meal ideas but to be honest we personally cannot afford the ingredients for so much variety.

Evening meals we have regularly are bolognese, curry, stir fry, jacket potato, risotto, quesadillas/wraps, roast, carbonara, cottage pie, soup, omelette.

My go-to cheap meal is pasta with a tomato sauce and just whatever veg/lentils/meat/cheese that we have thrown in. You can make an easy sauce with tinned tomatoes and a stock cube and some dried herbs x