My whole family has eaten dairy free for the majority of the last 5 years, as all 3 dc have been intolerant until around age 2 (well, we don't know when dc3 will outgrow intolerance, as he's only 8 months atm).
We just skip meals that need cheese as the substitutes are universally vile. Some meals that we have are:
shepherds pie - add butternut squash and/or sweet potato to normal potato for the topping, and it really doesn't need much if any butter.
chicken and cauliflower curry with coconut milk
spag bol
mild chilli
moroccan chicken
omelette
fish fingers/ fish and chips
fish pie (either make white sauce using oat milk, or make it a bit cheesy using toffuti, a soft cheese which I get from holland and barrett).
salmon and coconut pasta
meatballs
stir fry
fajitas
corn fritters
falafel or sweet potato falafel
kedgeree (I use an old slimming world recipe with eggs rather than smoked fish)
beef or lamb stew and dumplings
sausage and mash
toad in the hole (oat milk makes good batter)
chickena and tarragon casserole (finish it with a splash of alpro fresh soya cream)
carribean peanut chicken
cassoulet
stuffed peppers
pies
As others have mentioned, use pure sunflower spread, vitalite, or M&S dairy free spread instead of butter.
Use Oatly with added calcium for milk (not the organic one, as no calcium). Rice milk is not recommended for under 5's any more due to arsenic levels. You can also get Kara calcium enriched milk made from coconuts, or hemp milk (I've bought some but haven't tried this one yet).
I choose not to use soya milk and would recommend against it for regular use in a child so young.
If you are breastfeeding then are you not giving up dairy yourself too, as cows milk protein does pass into breast milk?