OP, as someone else mentioned, groceries are way cheaper in the states. Whenever I visit my family in Massachusetts, I'm always blown away by 1) the amount of choices there are in US groceries stores for a particular item (brands, etc), and 2) the prices compared to Canada.
I'd never really bothered to see how much we spend on food in a month - food, household expenses, gas, car repairs, and shared activities all come out of our joint account, and it usually comes out to 1000$ a month. However, I just did a quick 3-month average, and it seems that we spend approximately 475$ CAD per month on food and household goods (cleaning supplies, toilet paper, shampoo, etc). This includes any time we eat out, as well as alcohol at the SAQ.
The way we get this to be so low, even for Québec, is firstly, by shopping Costco approximately every 2 months. I understand not having room, we also live in a condo (loft-style) and don't have room for (nor do we want) a chest freezer. However, I'm able to store about a month's worth of meat/fish in my freezer. I cook every night, a 4-person meal (2-person dinner + 2-person lunches for the next day), so I don't take up room in my freezer with any pre-made meals. That's the biggest help I've found - not taking up room in my freezer with tuperware.
Other than that, we buy 10 kg bags of rice (easy to store in the pantry), and eat a ton of vegetables (in-season mostly). My partner is a carnivore, so there has to be meat or fish, but I make it stretch by putting a lot of veggies mixed in, and I buy sale meat (mostly pork, chicken, and a lot of fish). We haven't had seafood in a while because it's so expensive, and beef is a rarity since it spiked in price. The slow-cooker is your friend in terms of buying crappier pieces of cheap meat - an ugly piece of pork will be delicious after spending a day in the slow-cooker.
The only "quick" meals we have are 4-packs of costco frozen cheese pizza (removed from the box to take up less room in the freezer) that we fancify with whatever is in the fridge on those nights I don't feel like cooking. Cans of tuna, 700 g containers of feta cheese from costco, eggs, veggies and some pita bread or tortillas are great for those rare times I didn't make enough for two lunches.
I'll be honest, I don't meal-plan before going to the grocery store. I make sure I have a stocked spice rack and pantry with necessities (oil, vinegars, soy sauce, coconut milk, whatever else you like). I shop my three grocery stores (bulk dry goods store, bulk fruit and vegetable store - or small ethnic stores are great to replace both of these, and a low-cost grocery store - Super C in my case), and then Costco every few months. Whatever is on sale or not too expensive, I buy, making sure that I have enough ingredients for each category (veggies, fruits, proteins, starches, etc). Then, I combine whatever I have throughout the week. This way, the prices dictate what I eat, instead of forcing myself to buy something just because a recipe calls for it.
I buy whatever is cheapest in the protein and middle aisle categories (dry goods), and I find the middle ground between whatever is cheapest and whatever is local in terms of fruits and vegetables. Also, especially for non perishable items, I always look at cost per kg, not cheapest overall.
It takes time to get the hang of it, but eventually you'll get to your chosen budget!